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xsLUk49wH4UD7e5KxYZQp
maths
parabola
tangent-to-parabola
Let P be a point on the parabola, x<sup>2</sup> = 4y. If the distance of P from the center of the circle, x<sup>2</sup> + y<sup>2</sup> + 6x + 8 = 0 is minimum, then the equation of the tangent to the parabola at P, is :
[{"identifier": "A", "content": "x + 4y $$-$$ 2 = 0"}, {"identifier": "B", "content": "x $$-$$ y + 3 = 0"}, {"identifier": "C", "content": "x + y +1 = 0"}, {"identifier": "D", "content": "x + 2y = 0"}]
["C"]
null
Let P(2t, t<sup>2</sup>) be any point on the parabola. <br><br>Center of the given circle C = ($$-$$ g, $$-$$f) = ($$-$$3, 0) <br><br>For PC to be minimum, it must be the normal to the parabola at P. <br><br>Slope of line PC = $${{{y_2} - {y_1}} \over {{x_2} - {x_1}}}$$ = $${{{t^2} - 0} \over {2t + 3}}$$ <br><br>Also,...
mcq
jee-main-2018-online-16th-april-morning-slot
7,327
tfGX1dpaJzWJ28zbkVzsK
maths
parabola
tangent-to-parabola
The equation of a tangent to the parabola, x<sup>2</sup> = 8y, which makes an angle $$\theta $$ with the positive directions of x-axis, is :
[{"identifier": "A", "content": "x = y cot $$\\theta $$ \u2013 2 tan $$\\theta $$"}, {"identifier": "B", "content": "y = x tan $$\\theta $$ + 2 cot $$\\theta $$"}, {"identifier": "C", "content": "x = y cot $$\\theta $$ + 2 tan $$\\theta $$"}, {"identifier": "D", "content": "y = x tan $$\\theta $$ \u2013 2 cot $$\\theta...
["C"]
null
x<sup>2</sup> = 8y <br><br>$$ \Rightarrow $$&nbsp;&nbsp;$${{dy} \over {dx}} = {x \over 4} = \tan \theta $$ <br><br>$$ \therefore $$&nbsp;&nbsp;x<sub>1</sub> = 4tan$$\theta $$ <br><br>y<sub>1</sub> = 2 tan<sup>2</sup> $$\theta $$ <br><br>Equation of tangent :- <br><br>y $$-$$ 2tan<sup>2</sup>$$\theta $$ = tan$$\theta $$...
mcq
jee-main-2019-online-12th-january-evening-slot
7,328
EqKHlIkAheyQcWlaj6wsQ
maths
parabola
tangent-to-parabola
The shortest distance between the line y = x and the curve y<sup>2</sup> = x – 2 is :
[{"identifier": "A", "content": "$$7\\over 4 \\sqrt2$$"}, {"identifier": "B", "content": "$$7\\over8$$"}, {"identifier": "C", "content": "$$11\\over 4 \\sqrt2$$"}, {"identifier": "D", "content": "2"}]
["A"]
null
<picture><source media="(max-width: 320px)" srcset="https://res.cloudinary.com/dckxllbjy/image/upload/v1734265259/exam_images/zea3n7u2udoo4a4xhtuv.webp"><source media="(max-width: 500px)" srcset="https://res.cloudinary.com/dckxllbjy/image/upload/v1734264552/exam_images/fmvqf3yjti1z1cuq9efe.webp"><img src="https://res.c...
mcq
jee-main-2019-online-8th-april-morning-slot
7,329
94sPnL19Hkkpr7KAvIN4n
maths
parabola
tangent-to-parabola
The tangent to the parabola y<sup>2</sup> = 4x at the point where it intersects the circle x<sup>2</sup> + y<sup>2</sup> = 5 in the first quadrant, passes through the point :
[{"identifier": "A", "content": "$$\\left( { - {1 \\over 4},{1 \\over 2}} \\right)$$"}, {"identifier": "B", "content": "$$\\left( { - {1 \\over 3},{4 \\over 3}} \\right)$$"}, {"identifier": "C", "content": "$$\\left( { {3 \\over 4},{7 \\over 4}} \\right)$$"}, {"identifier": "D", "content": "$$\\left( { {1 \\over 4},{3 ...
["C"]
null
Parabola y<sup>2</sup> = 4x and circle x<sup>2</sup> + y<sup>2</sup> = 5 intersect with each other. <br><br>So, x<sup>2</sup> + 4x = 5 <br><br>$$ \Rightarrow $$ x<sup>2</sup> + 5x – x – 5 = 0 <br><br>$$ \Rightarrow $$ x(x + 5) –1(x + 5) = 0 <br><br> x = 1, –5 <br><br>Intersection point in 1<sup>st</sup> quadrant is ...
mcq
jee-main-2019-online-8th-april-evening-slot
7,330
Qzo3zWtSFrtM4esOgF7k9k2k5e2t4o5
maths
parabola
tangent-to-parabola
If y = mx + 4 is a tangent to both the parabolas, y<sup>2</sup> = 4x and x<sup>2</sup> = 2by, then b is equal to :
[{"identifier": "A", "content": "-128"}, {"identifier": "B", "content": "128"}, {"identifier": "C", "content": "-64"}, {"identifier": "D", "content": "-32"}]
["A"]
null
Given y = mx + 4 is tangent to both the parabolas. <br><br>$$ \therefore $$ Applying condition of tangent for y<sup>2</sup> = 4x, we get <br><br>$${1 \over m}$$ = 4 <br><br>$$ \Rightarrow $$ m = $${1 \over 4}$$ <br><br>For x<sup>2</sup> = 2by line y = $${x \over 4}$$ + 4 is tangent <br><br>$$ \therefore $$ x<sup>2</...
mcq
jee-main-2020-online-7th-january-morning-slot
7,332
rfhigTYGjSTU3SfhyM7k9k2k5hkcpya
maths
parabola
tangent-to-parabola
Let a line y = mx (m &gt; 0) intersect the parabola, y<sup>2</sup> = x at a point P, other than the origin. Let the tangent to it at P meet the x-axis at the point Q. If area ($$\Delta $$OPQ) = 4 sq. units, then m is equal to __________.
[]
null
0.5
<img src="https://res.cloudinary.com/dckxllbjy/image/upload/v1734263897/exam_images/dzexdmaraqpgczbig0ch.webp" style="max-width: 100%;height: auto;display: block;margin: 0 auto;" loading="lazy" alt="JEE Main 2020 (Online) 8th January Evening Slot Mathematics - Parabola Question 81 English Explanation"> <br><br>let P(t<...
integer
jee-main-2020-online-8th-january-evening-slot
7,333
n22hr3tMIhzdm87QTs7k9k2k5khbjd9
maths
parabola
tangent-to-parabola
If one end of a focal chord AB of the parabola y<sup>2</sup> = 8x is at $$A\left( {{1 \over 2}, - 2} \right)$$, then the equation of the tangent to it at B is :
[{"identifier": "A", "content": "2x \u2013 y \u2013 24 = 0"}, {"identifier": "B", "content": "x \u2013 2y + 8 = 0"}, {"identifier": "C", "content": "x + 2y + 8 = 0"}, {"identifier": "D", "content": "2x + y \u2013 24 = 0"}]
["B"]
null
Given parabola y<sup>2</sup> = 8x <br><br> $$ \therefore $$ a = 2 <br><br>Let one end of focal chord is A(at<sup>2</sup> , 2at) = $$\left( {{1 \over 2}, - 2} \right)$$ <br><br>$$ \therefore $$ 2at = -2 <br><br>$$ \Rightarrow $$ t = $$ - {1 \over 2}$$ <br><br>Other end of focal chord will be B$$\left( {{a \over {{t^2}}...
mcq
jee-main-2020-online-9th-january-evening-slot
7,334
GPFzk7LGXaUuo4pZZRjgy2xukg0ca10s
maths
parabola
tangent-to-parabola
The centre of the circle passing through the point (0, 1) and touching the parabola <br/>y = x<sup>2</sup> at the point (2, 4) is :
[{"identifier": "A", "content": "$$\\left( {{6 \\over 5},{{53} \\over {10}}} \\right)$$"}, {"identifier": "B", "content": "$$\\left( {{3 \\over {10}},{{16} \\over 5}} \\right)$$"}, {"identifier": "C", "content": "$$\\left( {{{ - 53} \\over {10}},{{16} \\over 5}} \\right)$$"}, {"identifier": "D", "content": "$$\\left( {...
["D"]
null
Circle passes through A(0, 1) and B(2, 4). <br><br>y = x<sup>2</sup> <br><br>$$ \Rightarrow $$ $${\left. {{{dy} \over {dx}}} \right|_B}$$ = 4 <br><br>tangent at (2,4) is <br><br>(y – 4) = 4(x – 2) <br><br>4x – y – 4 = 0 <br><br>Equation of circle <br><br>(x - 2)<sup>2</sup> + (y–4)<sup>2</sup> + $$\lambda $$(4x–y - ...
mcq
jee-main-2020-online-6th-september-evening-slot
7,336
WDNtK3CUUqbHxvqP2a1kls4ew0l
maths
parabola
tangent-to-parabola
A tangent is drawn to the parabola y<sup>2</sup> = 6x which is perpendicular to the line 2x + y = 1. Which of the following points does NOT lie on it?
[{"identifier": "A", "content": "(0, 3)"}, {"identifier": "B", "content": "($$-$$6, 0)"}, {"identifier": "C", "content": "(4, 5)"}, {"identifier": "D", "content": "(5, 4)"}]
["D"]
null
Equation of tangent : $$y = mx + {3 \over {2m}}$$<br><br>$${m_T} = {1 \over 2}$$ ($$\because$$ perpendicular to line $$2x + y = 1$$)<br><br>$$\therefore$$ tangent is : $$y = {x \over 2} + 3$$<br><br>$$ \Rightarrow x - 2y + 6 = 0$$
mcq
jee-main-2021-online-25th-february-morning-slot
7,337
jruZYQyLd3qh7eYuel1kmix5bse
maths
parabola
tangent-to-parabola
Let C be the locus of the mirror image of a point on the parabola y<sup>2</sup> = 4x with respect to the line y = x. Then the equation of tangent to C at P(2, 1) is :
[{"identifier": "A", "content": "x $$-$$ y = 1"}, {"identifier": "B", "content": "2x + y = 5"}, {"identifier": "C", "content": "x + 3y = 5"}, {"identifier": "D", "content": "x + 2y = 4"}]
["A"]
null
<img src="https://res.cloudinary.com/dckxllbjy/image/upload/v1734264947/exam_images/axoyq3cd2jeffcuzpst3.webp" style="max-width: 100%;height: auto;display: block;margin: 0 auto;" loading="lazy" alt="JEE Main 2021 (Online) 16th March Evening Shift Mathematics - Parabola Question 66 English Explanation"> <br>Image of y<s...
mcq
jee-main-2021-online-16th-march-evening-shift
7,338
1krw132tm
maths
parabola
tangent-to-parabola
Let a parabola b be such that its vertex and focus lie on the positive x-axis at a distance 2 and 4 units from the origin, respectively. If tangents are drawn from O(0, 0) to the parabola P which meet P at S and R, then the area (in sq. units) of $$\Delta$$SOR is equal to :
[{"identifier": "A", "content": "$$16\\sqrt 2 $$"}, {"identifier": "B", "content": "16"}, {"identifier": "C", "content": "32"}, {"identifier": "D", "content": "$$8\\sqrt 2 $$"}]
["B"]
null
<img src="https://res.cloudinary.com/dckxllbjy/image/upload/v1734264154/exam_images/jj7xl6x9z7rdt8utfb0x.webp" style="max-width: 100%;height: auto;display: block;margin: 0 auto;" loading="lazy" alt="JEE Main 2021 (Online) 25th July Morning Shift Mathematics - Parabola Question 60 English Explanation"><br>Clearly RS is ...
mcq
jee-main-2021-online-25th-july-morning-shift
7,340
1l57p81t3
maths
parabola
tangent-to-parabola
<p>A circle of radius 2 unit passes through the vertex and the focus of the parabola y<sup>2</sup> = 2x and touches the parabola $$y = {\left( {x - {1 \over 4}} \right)^2} + \alpha $$, where $$\alpha$$ &gt; 0. Then (4$$\alpha$$ $$-$$ 8)<sup>2</sup> is equal to ______________.</p>
[]
null
63
<p><img src="https://app-content.cdn.examgoal.net/fly/@width/image/1l5qa7f14/20481fc2-2f60-4c10-b833-b651bfbff5ae/fd4dc580-0656-11ed-903e-c9687588b3f3/file-1l5qa7f15.png?format=png" data-orsrc="https://app-content.cdn.examgoal.net/image/1l5qa7f14/20481fc2-2f60-4c10-b833-b651bfbff5ae/fd4dc580-0656-11ed-903e-c9687588b3f3...
integer
jee-main-2022-online-27th-june-morning-shift
7,342
1l59kykzv
maths
parabola
tangent-to-parabola
<p>If the line $$y = 4 + kx,\,k &gt; 0$$, is the tangent to the parabola $$y = x - {x^2}$$ at the point P and V is the vertex of the parabola, then the slope of the line through P and V is :</p>
[{"identifier": "A", "content": "$${3 \\over 2}$$"}, {"identifier": "B", "content": "$${26 \\over 9}$$"}, {"identifier": "C", "content": "$${5 \\over 2}$$"}, {"identifier": "D", "content": "$${23 \\over 6}$$"}]
["C"]
null
<p>$$\because$$ Line $$y = kx + 4$$ touches the parabola $$y = x - {x^2}$$.</p> <p>So, $$kx + 4 = x - {x^2} \Rightarrow {x^2} + (k - 1)x + 4 = 0$$ has only one root</p> <p>$${(k - 1)^2} = 16 \Rightarrow k = 5$$ or $$-$$3 but $$k > 0$$</p> <p>So, $$k = 5$$.</p> <p>And hence $${x^2} + 4x + 4 = 0 \Rightarrow x = - 2$$</p...
mcq
jee-main-2022-online-25th-june-evening-shift
7,343
1l6dxgu1l
maths
parabola
tangent-to-parabola
<p>The sum of diameters of the circles that touch (i) the parabola $$75 x^{2}=64(5 y-3)$$ at the point $$\left(\frac{8}{5}, \frac{6}{5}\right)$$ and (ii) the $$y$$-axis, is equal to ______________.</p>
[]
null
10
<img src="https://app-content.cdn.examgoal.net/fly/@width/image/1l97t0fy1/82aaf9b5-d36f-45fe-b435-ffafbaba2be0/81fa0a90-4b5e-11ed-bfde-e1cb3fafe700/file-1l97t0fy2.png?format=png" data-orsrc="https://app-content.cdn.examgoal.net/image/1l97t0fy1/82aaf9b5-d36f-45fe-b435-ffafbaba2be0/81fa0a90-4b5e-11ed-bfde-e1cb3fafe700/fi...
integer
jee-main-2022-online-25th-july-morning-shift
7,344
1l6f1mr40
maths
parabola
tangent-to-parabola
<p>The tangents at the points $$A(1,3)$$ and $$B(1,-1)$$ on the parabola $$y^{2}-2 x-2 y=1$$ meet at the point $$P$$. Then the area (in unit $${ }^{2}$$ ) of the triangle $$P A B$$ is :</p>
[{"identifier": "A", "content": "4"}, {"identifier": "B", "content": "6"}, {"identifier": "C", "content": "7"}, {"identifier": "D", "content": "8"}]
["D"]
null
<p>Given curve : $${y^2} - 2x - 2y = 1$$.</p> <p>Can be written as</p> <p>$${(y - 1)^2} = 2(x + 1)$$</p> <p><img src="https://app-content.cdn.examgoal.net/fly/@width/image/1l7bummn7/86c95a3b-4fff-4748-b770-5b447b8c82d7/87ebf730-25ff-11ed-9c74-c5a04899a045/file-1l7bummn8.png?format=png" data-orsrc="https://app-content.c...
mcq
jee-main-2022-online-25th-july-evening-shift
7,345
ldoadhnb
maths
parabola
tangent-to-parabola
Let $\mathrm{S}$ be the set of all $\mathrm{a} \in \mathrm{N}$ such that the area of the triangle formed by the tangent at the point $\mathrm{P}(\mathrm{b}$, c), b, c $\in \mathbb{N}$, on the parabola $y^{2}=2 \mathrm{a} x$ and the lines $x=\mathrm{b}, y=0$ is $16 $ unit<sup>2</sup>, then $\sum\limits_{\mathrm{a} \in \...
[]
null
146
<img src="https://app-content.cdn.examgoal.net/fly/@width/image/1lefxfag8/8b4831e9-648d-41a1-9ba1-f0f0ff15128a/1d79d280-b2d3-11ed-8169-e1635469e777/file-1lefxfag9.png?format=png" data-orsrc="https://app-content.cdn.examgoal.net/image/1lefxfag8/8b4831e9-648d-41a1-9ba1-f0f0ff15128a/1d79d280-b2d3-11ed-8169-e1635469e777/fi...
integer
jee-main-2023-online-31st-january-evening-shift
7,349
1ldptdxi9
maths
parabola
tangent-to-parabola
<p>Let $$\mathrm{y}=f(x)$$ represent a parabola with focus $$\left(-\frac{1}{2}, 0\right)$$ and directrix $$y=-\frac{1}{2}$$. Then <br/><br/>$$S=\left\{x \in \mathbb{R}: \tan ^{-1}(\sqrt{f(x)})+\sin ^{-1}(\sqrt{f(x)+1})=\frac{\pi}{2}\right\}$$ :</p>
[{"identifier": "A", "content": "is an empty set"}, {"identifier": "B", "content": "contains exactly one element"}, {"identifier": "C", "content": "contains exactly two elements"}, {"identifier": "D", "content": "is an infinite set"}]
["C"]
null
$\left(x+\frac{1}{2}\right)^{2}=\left(y+\frac{1}{4}\right)$ <br/><br/>$y=\left(x^{2}+x\right)$ <br/><br/>$\tan ^{-1} \sqrt{\mathrm{x}(\mathrm{x}+1)}+\sin ^{-1} \sqrt{\mathrm{x}^{2}+\mathrm{x}+1}=\pi / 2$ <br/><br/>$0 \leq \mathrm{x}^{2}+\mathrm{x}+1 \leq 1$ <br/><br/>$x^{2}+x \leq 0$ <br/><br/>Also $x^{2}+x \geq 0...
mcq
jee-main-2023-online-31st-january-morning-shift
7,350
1ldsf5fpj
maths
parabola
tangent-to-parabola
<p>If the tangent at a point P on the parabola $$y^2=3x$$ is parallel to the line $$x+2y=1$$ and the tangents at the points Q and R on the ellipse $$\frac{x^2}{4}+\frac{y^2}{1}=1$$ are perpendicular to the line $$x-y=2$$, then the area of the triangle PQR is :</p>
[{"identifier": "A", "content": "$$\\frac{9}{\\sqrt5}$$"}, {"identifier": "B", "content": "$$3\\sqrt5$$"}, {"identifier": "C", "content": "$$5\\sqrt3$$"}, {"identifier": "D", "content": "$$\\frac{3}{2}\\sqrt5$$"}]
["B"]
null
<p>$$P \equiv \left( {{A \over {{m^2}}},{{2A} \over m}} \right)$$ where $$\left( {A = {3 \over 4},m = {{ - 1} \over 2}} \right)$$</p> <p>& $$Q,R = \left( { \mp \,{{{a^2}{m_1}} \over {{a^2}m_1^2 + {b^2}}},{{ \mp \,.\,{b^2}} \over {\sqrt {{a^2}m_1^2 + {b^2}} }}} \right)$$</p> <p>Where $${a^2} = 4,{b^2} = 1$$ and $${m_1} ...
mcq
jee-main-2023-online-29th-january-evening-shift
7,351
1ldwwuxyg
maths
parabola
tangent-to-parabola
<p>The equations of the sides AB and AC of a triangle ABC are $$(\lambda+1)x+\lambda y=4$$ and $$\lambda x+(1-\lambda)y+\lambda=0$$ respectively. Its vertex A is on the y-axis and its orthocentre is (1, 2). The length of the tangent from the point C to the part of the parabola $$y^2=6x$$ in the first quadrant is :</p>
[{"identifier": "A", "content": "4"}, {"identifier": "B", "content": "2$$\\sqrt2$$"}, {"identifier": "C", "content": "2"}, {"identifier": "D", "content": "$$\\sqrt6$$"}]
["B"]
null
$$ \begin{aligned} &amp; \mathrm{AB}:(\lambda+1) x+\lambda y=4 \\\\ &amp; \mathrm{AC}: \lambda x+(1-\lambda) y+\lambda=0 \\\\ &amp; \text { Vertex } A \text { is on } y \text {-axis } \\\\ &amp; \Rightarrow x=0 \end{aligned} $$<br><br> <img src="https://app-content.cdn.examgoal.net/fly/@width/image/1le5hgrn5/44884087-b...
mcq
jee-main-2023-online-24th-january-evening-shift
7,353
1ldyamg53
maths
parabola
tangent-to-parabola
<p>Let a tangent to the curve $$\mathrm{y^2=24x}$$ meet the curve $$xy = 2$$ at the points A and B. Then the mid points of such line segments AB lie on a parabola with the :</p>
[{"identifier": "A", "content": "length of latus rectum 2"}, {"identifier": "B", "content": "directrix 4x = $$-$$3"}, {"identifier": "C", "content": "directrix 4x = 3"}, {"identifier": "D", "content": "length of latus rectum $$\\frac{3}{2}$$"}]
["C"]
null
<p><img src="https://app-content.cdn.examgoal.net/fly/@width/image/1le2n7sz9/699005b2-a3c2-4567-bfdf-626597fbe0f4/0194ea50-ab85-11ed-bcb9-87e2bc2e0c49/file-1le2n7sza.png?format=png" data-orsrc="https://app-content.cdn.examgoal.net/image/1le2n7sz9/699005b2-a3c2-4567-bfdf-626597fbe0f4/0194ea50-ab85-11ed-bcb9-87e2bc2e0c49...
mcq
jee-main-2023-online-24th-january-morning-shift
7,354
1lgym0ipz
maths
parabola
tangent-to-parabola
<p>Let $$\mathrm{A}(0,1), \mathrm{B}(1,1)$$ and $$\mathrm{C}(1,0)$$ be the mid-points of the sides of a triangle with incentre at the point $$\mathrm{D}$$. If the focus of the parabola $$y^{2}=4 \mathrm{ax}$$ passing through $$\mathrm{D}$$ is $$(\alpha+\beta \sqrt{2}, 0)$$, where $$\alpha$$ and $$\beta$$ are rational n...
[{"identifier": "A", "content": "$$\\frac{9}{2}$$"}, {"identifier": "B", "content": "12"}, {"identifier": "C", "content": "6"}, {"identifier": "D", "content": "8"}]
["D"]
null
<img src="https://app-content.cdn.examgoal.net/fly/@width/image/6y3zli1lmyvdpob/0009489a-90f2-422f-89e7-7c971c77552a/bebae0b0-5b9f-11ee-b31c-37f6bf9b942e/file-6y3zli1lmyvdpoc.png?format=png" data-orsrc="https://app-content.cdn.examgoal.net/image/6y3zli1lmyvdpob/0009489a-90f2-422f-89e7-7c971c77552a/bebae0b0-5b9f-11ee-b3...
mcq
jee-main-2023-online-8th-april-evening-shift
7,355
lv9s20p5
maths
parabola
tangent-to-parabola
<p>Let a line perpendicular to the line $$2 x-y=10$$ touch the parabola $$y^2=4(x-9)$$ at the point P. The distance of the point P from the centre of the circle $$x^2+y^2-14 x-8 y+56=0$$ is __________.</p>
[]
null
10
<p>Line perpendicular to $$2 x-y=10$$ have slope $$=\frac{-1}{2}$$</p> <p>$$\Rightarrow$$ Line tangent to parabola $$y^2=4(x-9)$$ with slope $$m$$ is</p> <p>$$\begin{aligned} & y=m(x-9)+\frac{1}{m}, m=\frac{-1}{2} \\ & \Rightarrow y=\frac{-(x-9)}{2}-2 \Rightarrow 2 y=-x+9-4 \\ & \Rightarrow 2 y+x=5 \end{aligned}$$</p> ...
integer
jee-main-2024-online-5th-april-evening-shift
7,357
lvc57noi
maths
parabola
tangent-to-parabola
<p>Let a conic $$C$$ pass through the point $$(4,-2)$$ and $$P(x, y), x \geq 3$$, be any point on $$C$$. Let the slope of the line touching the conic $$C$$ only at a single point $$P$$ be half the slope of the line joining the points $$P$$ and $$(3,-5)$$. If the focal distance of the point $$(7,1)$$ on $$C$$ is $$d$$, ...
[]
null
75
<p>As per given condition</p> <p>$$\begin{gathered} \frac{d y}{d x}=\frac{y+5}{2(x-3)} \\ \Rightarrow \ln (y+5)=\frac{1}{2} \ln (x-3)+c \\ \text { Passes through }(4,-2) \Rightarrow \ln 3=\frac{1}{2} \ln 1+c \\ \Rightarrow c=\ln 3 \end{gathered}$$</p> <p>$$\Rightarrow$$ Curve is $$(y+5)^2=9(x-3)$$</p> <p>Focal distance...
integer
jee-main-2024-online-6th-april-morning-shift
7,358
lvc583gl
maths
parabola
tangent-to-parabola
<p>Let $$L_1, L_2$$ be the lines passing through the point $$P(0,1)$$ and touching the parabola $$9 x^2+12 x+18 y-14=0$$. Let $$Q$$ and $$R$$ be the points on the lines $$L_1$$ and $$L_2$$ such that the $$\triangle P Q R$$ is an isosceles triangle with base $$Q R$$. If the slopes of the lines $$Q R$$ are $$m_1$$ and $$...
[]
null
68
<p>$$\begin{aligned} &amp; 9 x^2+12 x+18 y-14=0 \\ &amp; \left(x+\frac{2}{3}\right)^2=-2(y-1) \ldots(1) \end{aligned}$$</p> <p>Equation of tangent to (1)</p> <p>$$\begin{aligned} &amp; t\left(x+\frac{2}{3}\right)=-(y-1)+\frac{1}{2} t^2 \text { passes through }(0,1) \\ &amp; \Rightarrow \frac{2}{3} t=\frac{1}{2} t^2 \Ri...
integer
jee-main-2024-online-6th-april-morning-shift
7,359
UbyEKAsad53b322QnPdNK
maths
permutations-and-combinations
application-of-permutations-and-combination-in-geometry
Let S be the set of all triangles in the xy-plane, each having one vertex at the origin and the other two vertices lie on coordinate axes with integral coordinates. If each triangle in S has area 50 sq. units, then the number of elements in the set S is :
[{"identifier": "A", "content": "9"}, {"identifier": "B", "content": "18"}, {"identifier": "C", "content": "36"}, {"identifier": "D", "content": "32"}]
["C"]
null
<img src="https://res.cloudinary.com/dckxllbjy/image/upload/v1734266952/exam_images/idxhu7dj3nmxsx1ackba.webp" style="max-width: 100%; height: auto;display: block;margin: 0 auto;" loading="lazy" alt="JEE Main 2019 (Online) 9th January Evening Slot Mathematics - Permutations and Combinations Question 143 English Explan...
mcq
jee-main-2019-online-9th-january-evening-slot
7,360
eOF6fmsz4KXubATcSH3rsa0w2w9jx2ay4se
maths
permutations-and-combinations
application-of-permutations-and-combination-in-geometry
Suppose that 20 pillars of the same height have been erected along the boundary of a circular stadium. If the top of each pillar has been connected by beams with the top of all its non-adjacent pillars, then the total number of beams is :
[{"identifier": "A", "content": "180"}, {"identifier": "B", "content": "210"}, {"identifier": "C", "content": "170"}, {"identifier": "D", "content": "190"}]
["C"]
null
<img src="https://res.cloudinary.com/dckxllbjy/image/upload/v1734264617/exam_images/eimc4dj1il40k9qseeao.webp" style="max-width: 100%; height: auto;display: block;margin: 0 auto;" loading="lazy" alt="JEE Main 2019 (Online) 10th April Evening Slot Mathematics - Permutations and Combinations Question 134 English Explana...
mcq
jee-main-2019-online-10th-april-evening-slot
7,361
I5Ortna4ugLS6ar8gn1kmiwfm5s
maths
permutations-and-combinations
application-of-permutations-and-combination-in-geometry
Consider a rectangle ABCD having 5, 7, 6, 9 points in the interior of the line segments AB, CD, BC, DA respectively. Let $$\alpha$$ be the number of triangles having these points from different sides as vertices and $$\beta$$ be the number of quadrilaterals having these points from different sides as vertices. Then ($$...
[{"identifier": "A", "content": "717"}, {"identifier": "B", "content": "795"}, {"identifier": "C", "content": "1890"}, {"identifier": "D", "content": "1173"}]
["A"]
null
$$\alpha = {}^6{C_1}{}^7{C_1}{}^9{C_1} + {}^5{C_1}{}^7{C_1}{}^9{C_1} + {}^5{C_1}{}^6{C_1}{}^9{C_1} + {}^5{C_1}{}^6{C_1}{}^7{C_1} $$ <br><br>$$= 378 + 315 + 270 + 210 = 1173$$<br><br>$$\beta = {}^5{C_1}{}^6{C_1}{}^7{C_1}{}^9{C_1} = 1890$$<br><br>$$ \therefore $$ $$ \beta - \alpha = 1890 - 1173 = 717$$
mcq
jee-main-2021-online-16th-march-evening-shift
7,362
uTYPsLQsZvZrwoOMNL1kmkl4mb8
maths
permutations-and-combinations
application-of-permutations-and-combination-in-geometry
If the sides AB, BC and CA of a triangle ABC have 3, 5 and 6 interior points respectively, then the total number of triangles that can be constructed using these points as vertices, is equal to :
[{"identifier": "A", "content": "240"}, {"identifier": "B", "content": "360"}, {"identifier": "C", "content": "333"}, {"identifier": "D", "content": "364"}]
["C"]
null
<img src="https://res.cloudinary.com/dckxllbjy/image/upload/v1734266804/exam_images/l90mpotax9t4vio9u3us.webp" style="max-width: 100%;height: auto;display: block;margin: 0 auto;" loading="lazy" alt="JEE Main 2021 (Online) 17th March Evening Shift Mathematics - Permutations and Combinations Question 106 English Explanat...
mcq
jee-main-2021-online-17th-march-evening-shift
7,363
1kto82i38
maths
permutations-and-combinations
application-of-permutations-and-combination-in-geometry
Let P<sub>1</sub>, P<sub>2</sub>, ......, P<sub>15</sub> be 15 points on a circle. The number of distinct triangles formed by points P<sub>i</sub>, P<sub>j</sub>, P<sub>k</sub> such that i +j + k $$\ne$$ 15, is :
[{"identifier": "A", "content": "12"}, {"identifier": "B", "content": "419"}, {"identifier": "C", "content": "443"}, {"identifier": "D", "content": "455"}]
["C"]
null
Total number of triangles = $${}^{15}{C_3}$$<br><br>i + j + k = 15 (Given)<br><br><img src="https://app-content.cdn.examgoal.net/fly/@width/image/1kwoq1bj3/a1cd0f3a-86a8-4d72-98ac-6d132a8be6f4/621a22f0-534d-11ec-9cbb-695a838b20fb/file-1kwoq1bj4.png?format=png" data-orsrc="https://app-content.cdn.examgoal.net/image/1kwo...
mcq
jee-main-2021-online-1st-september-evening-shift
7,364
1ldu601xz
maths
permutations-and-combinations
application-of-permutations-and-combination-in-geometry
<p>A triangle is formed by X-axis, Y-axis and the line $$3x+4y=60$$. Then the number of points P(a, b) which lie strictly inside the triangle, where a is an integer and b is a multiple of a, is ____________.</p>
[]
null
31
If x = 1, y = $57 \over 4 $ = 14.25<br><br><img src="https://app-content.cdn.examgoal.net/fly/@width/image/1lef6kjms/0eda98c6-e556-46f8-a286-86afedde79c5/1920a240-b26a-11ed-a7d3-67cb923c1f9d/file-1lef6kjmt.png?format=png" data-orsrc="https://app-content.cdn.examgoal.net/image/1lef6kjms/0eda98c6-e556-46f8-a286-86afedde7...
integer
jee-main-2023-online-25th-january-evening-shift
7,365
lvc57pix
maths
permutations-and-combinations
application-of-permutations-and-combination-in-geometry
<p>The number of triangles whose vertices are at the vertices of a regular octagon but none of whose sides is a side of the octagon is</p>
[{"identifier": "A", "content": "56"}, {"identifier": "B", "content": "16"}, {"identifier": "C", "content": "24"}, {"identifier": "D", "content": "48"}]
["B"]
null
<p>To solve this problem, we need to determine the number of triangles formed by the vertices of a regular octagon such that none of the sides of the triangle is also a side of the octagon.</p> <p>Let's start by counting the total number of triangles that can be formed using the 8 vertices of the octagon. The number o...
mcq
jee-main-2024-online-6th-april-morning-shift
7,367
EkC57Q2rx3Nbk6Jx
maths
permutations-and-combinations
circular-permutations
The number of ways in which 6 men and 5 women can dine at a round table if no two women are to sit together is given by
[{"identifier": "A", "content": "$$7!\\, \\times 5!\\,\\,$$ "}, {"identifier": "B", "content": "$$6!\\, \\times 5!$$ "}, {"identifier": "C", "content": "$$30!$$ "}, {"identifier": "D", "content": "$$5!\\, \\times 4!$$ "}]
["B"]
null
<img class="question-image" src="https://res.cloudinary.com/dckxllbjy/image/upload/v1734266135/exam_images/ihwshbrvypvoyv0j1fui.webp" loading="lazy" alt="AIEEE 2003 Mathematics - Permutations and Combinations Question 172 English Explanation 1"> <br><br>6 men can sit at the round table = $$\left( {6 - 1} \right)! = 5!$...
mcq
aieee-2003
7,368
J7rxWs0HNWj60oLGyuAiC
maths
permutations-and-combinations
circular-permutations
The number of ways in which 5 boys and 3 girls can be seated on a round table if a particular boy B<sub>1</sub> and a particular girl G<sub>1</sub> never sit adjacent to each other, is :
[{"identifier": "A", "content": "5 $$ \\times $$ 6!"}, {"identifier": "B", "content": "6 $$ \\times $$ 6!"}, {"identifier": "C", "content": "7!"}, {"identifier": "D", "content": "5 $$ \\times $$ 7!"}]
["A"]
null
Number of ways = Total - when B<sub>1</sub> and G<sub>1</sub> sit together <br><br>Total ways to seat 8 people on round table = (8 - 1)! = 7! <br><br>When B<sub>1</sub> and G<sub>1</sub> sit together then assume B<sub>1</sub> and G<sub>1</sub> are one people, so total 7 people are there and among B<sub>1</sub> and G<s...
mcq
jee-main-2017-online-9th-april-morning-slot
7,369
5PYzxgZ7ICeBa0uH9Ijgy2xukez5kjog
maths
permutations-and-combinations
circular-permutations
Let n &gt; 2 be an integer. Suppose that there are n Metro stations in a city located along a circular path. Each pair of stations is connected by a straight track only. Further, each pair of nearest stations is connected by blue line, whereas all remaining pairs of stations are connected by red line. If the number of ...
[{"identifier": "A", "content": "201"}, {"identifier": "B", "content": "199"}, {"identifier": "C", "content": "101"}, {"identifier": "D", "content": "200"}]
["A"]
null
<picture><source media="(max-width: 320px)" srcset="https://res.cloudinary.com/dckxllbjy/image/upload/v1734266330/exam_images/ui7cjccg9xqw9a5eyvuj.webp"><source media="(max-width: 500px)" srcset="https://res.cloudinary.com/dckxllbjy/image/upload/v1734267793/exam_images/ejhknnuxiul6gerikcuo.webp"><img src="https://res.c...
mcq
jee-main-2020-online-2nd-september-evening-slot
7,370
1lgzycfb1
maths
permutations-and-combinations
circular-permutations
<p>The number of ways, in which 5 girls and 7 boys can be seated at a round table so that no two girls sit together, is :</p>
[{"identifier": "A", "content": "720"}, {"identifier": "B", "content": "$$7(360)^{2}$$"}, {"identifier": "C", "content": "$$7(720)^{2}$$"}, {"identifier": "D", "content": "$$126(5 !)^{2}$$"}]
["D"]
null
We have, <br><br>Number of girls $=5$ <br><br>Number of boys $=7$ <br><br><img src="https://app-content.cdn.examgoal.net/fly/@width/image/6y3zli1lmltts5a/3a0ee79a-7b48-44a1-98c7-740fb4585474/7ae256d0-5473-11ee-9283-c929f40dddd4/file-6y3zli1lmltts5b.png?format=png" data-orsrc="https://app-content.cdn.examgoal.net/image/...
mcq
jee-main-2023-online-8th-april-morning-shift
7,371
Ya9LDYYS0XiNoh28
maths
permutations-and-combinations
conditional-combinations
A student is to answer 10 out of 13 questions in an examination such that he must choose at least 4 from the first five questions. The number of choices available to him is
[{"identifier": "A", "content": "346"}, {"identifier": "B", "content": "140"}, {"identifier": "C", "content": "196"}, {"identifier": "D", "content": "280"}]
["C"]
null
<img class="question-image" src="https://res.cloudinary.com/dckxllbjy/image/upload/v1734264044/exam_images/uld4peekswqjropomsze.webp" loading="lazy" alt="AIEEE 2003 Mathematics - Permutations and Combinations Question 173 English Explanation"> <br><br><b>Case 1 :</b> <br><br>No of ways student can answer 10 questions =...
mcq
aieee-2003
7,372
ynFU9TI4bBJDhzTbt7TZv
maths
permutations-and-combinations
conditional-combinations
A committee of 11 members is to be formed from 8 males and 5 females. If m is the number of ways the committee is formed with at least 6 males and n is the number of ways the committee is formed with at least 3 females, then :
[{"identifier": "A", "content": "n = m \u2013 8"}, {"identifier": "B", "content": "m = n = 78"}, {"identifier": "C", "content": "m + n = 68"}, {"identifier": "D", "content": "m = n = 68"}]
["B"]
null
At least 6 males means in the committee there can be 6 males or 7 males or 8 males. <br><br>$$ \therefore $$ m = $${}^8{C_6} \times {}^5{C_5} + {}^8{C_7} \times {}^5{C_4} + {}^8{C_8} \times {}^5{C_3}$$ = 78 <br><br>At least 3 females means in the committee there can be 3 females or 4 females or 5 females. <br><br>$$ \t...
mcq
jee-main-2019-online-9th-april-morning-slot
7,375
dGIKlgBoeVJkXafbxljgy2xukfjjsiul
maths
permutations-and-combinations
conditional-combinations
Four fair dice are thrown independently 27 times. Then the expected number of times, at least two dice show up a three or a five, is _________.
[]
null
11
4 dice are independently thrown. Each die has probability to show 3 or 5 is <br><br>$$P = {2 \over 6} = {1 \over 3}$$<br><br>$$ \therefore $$ $$q = 1 - {1 \over 3} = {2 \over 3}$$ (not showing 3 or 5)<br><br>Experiment is performed with 4 dices independently<br><br>$$ \therefore $$ Their binomial distribution is <br><b...
integer
jee-main-2020-online-5th-september-morning-slot
7,376
ogAhHOb39XAuEA27w1jgy2xukfqbzbjj
maths
permutations-and-combinations
conditional-combinations
There are 3 sections in a question paper and each section contains 5 questions. A candidate has to answer a total of 5 questions, choosing at least one question from each section. Then the number of ways, in which the candidate can choose the questions, is :
[{"identifier": "A", "content": "2250"}, {"identifier": "B", "content": "2255"}, {"identifier": "C", "content": "3000"}, {"identifier": "D", "content": "1500"}]
["A"]
null
<img src="https://res.cloudinary.com/dckxllbjy/image/upload/v1734265719/exam_images/cbjd8rqt5qx4eis3hsmv.webp" style="max-width: 100%;height: auto;display: block;margin: 0 auto;" loading="lazy" alt="JEE Main 2020 (Online) 5th September Evening Slot Mathematics - Permutations and Combinations Question 117 English Explan...
mcq
jee-main-2020-online-5th-september-evening-slot
7,377
kWZNAunq6lVQD0QwtP1klrg0wg0
maths
permutations-and-combinations
conditional-combinations
A scientific committee is to be formed from 6 Indians and 8 foreigners, which includes at least 2 Indians and double the number of foreigners as Indians. Then the number of ways, the committee can be formed, is :
[{"identifier": "A", "content": "1050"}, {"identifier": "B", "content": "575"}, {"identifier": "C", "content": "560"}, {"identifier": "D", "content": "1625"}]
["D"]
null
Given,<br/><br/>Number of Indians = 6<br/><br/>Number of foreigners = 8<br/><br/>Committee of at least 2 Indians and double number of foreigners is to be formed. Hence, the required cases are<br/><br/>(2I, 4F) + (3I, 6F) + (4I, 8F)<br/><br/>= $${}^6{C_2} \times {}^8{C_4} + {}^6{C_3} \times {}^8{C_6} + {}^6{C_4} \times ...
mcq
jee-main-2021-online-24th-february-morning-slot
7,378
xFuZjzUptaNFdoUgdM1klrmy2in
maths
permutations-and-combinations
conditional-combinations
The students S<sub>1</sub>, S<sub>2</sub>, ....., S<sub>10</sub> are to be divided into 3 groups A, B and C such that each group has at least one student and the group C has at most 3 students. Then the total number of possibilities of forming such groups is ___________.
[]
null
31650
If group C has one student then number of groups <br><br>= <sup>10</sup>C<sub>1</sub> [2<sup>9</sup> – 2] = 5100 <br><br>If group C has two students then number of groups <br><br>= <sup>10</sup>C<sub>2</sub> [2<sup>8</sup> – 2] = 11430 <br><br>If group C has three students then number of groups <br><br>= <sup>10</sup...
integer
jee-main-2021-online-24th-february-evening-slot
7,379
OtCzg7Sq3gsThouMtK1kls4fv1n
maths
permutations-and-combinations
conditional-combinations
The total number of positive integral solutions (x, y, z) such that xyz = 24 is :
[{"identifier": "A", "content": "36"}, {"identifier": "B", "content": "24"}, {"identifier": "C", "content": "45"}, {"identifier": "D", "content": "30"}]
["D"]
null
$$x.y.z = 24$$<br><br>$$x.y.z = {2^3}.\,{3^1}$$<br><br>Three 2 has to be distributed among x, y and z<br><br>Each may receive none, one or two<br><br>$$\therefore$$ Number of ways = $${}^{3 + 3 - 1}{C_{3 - 1}}$$ = $$^5{C_2}$$ ways<br><br>Similarly one 3 has to be distributed among x, y and z<br><br>$$ \therefore $$ Num...
mcq
jee-main-2021-online-25th-february-morning-slot
7,380
eNLKKMO5cYrCM8Jz6S1kluge0sz
maths
permutations-and-combinations
conditional-combinations
The number of seven digit integers with sum of the digits equal to 10 and formed by using the digits 1, 2 and 3 only is :
[{"identifier": "A", "content": "35"}, {"identifier": "B", "content": "42"}, {"identifier": "C", "content": "82"}, {"identifier": "D", "content": "77"}]
["D"]
null
(I) First possibility is 1, 1, 1, 1, 1, 2, 3<br><br>required number = $${{7!} \over {5!}}$$ = 7 $$\times$$ 6 = 42<br><br>(II) Second possibility is 1, 1, 1, 1, 2, 2, 2<br><br>required number = $${{7!} \over {4!3!}} = {{7 \times 6 \times 5} \over 6} = 35$$<br><br>Total = 42 + 35 = 77
mcq
jee-main-2021-online-26th-february-morning-slot
7,381
1krq1dvgf
maths
permutations-and-combinations
conditional-combinations
There are 15 players in a cricket team, out of which 6 are bowlers, 7 are batsman and 2 are wicketkeepers. The number of ways, a team of 11 players be selected from them so as to include at least 4 bowlers, 5 batsman and 1 wicketkeeper, is ______________.
[]
null
777
15 : Players<br><br>6 : Bowlers<br><br>7 : Batsman<br><br>2 : Wicket keepers<br><br>Total number of ways for :<br><br>at least 4 bowler, 5 batsman &amp; 1 wicket keeper<br><br>= $${}^6{C_4}({}^7{C_6} \times {}^2{C_1} + {}^7{C_5} \times {}^2{C_2}) + {}^6{C_5} \times {}^7{C_5} \times {}^2{C_1}$$<br><br>$$ = 777$$
integer
jee-main-2021-online-20th-july-morning-shift
7,382
1krw30swu
maths
permutations-and-combinations
conditional-combinations
There are 5 students in class 10, 6 students in class 11 and 8 students in class 12. If the number of ways, in which 10 students can be selected from them so as to include at least 2 students from each class and at most 5 students from the total 11 students of class 10 and 11 is 100 k, then k is equal to _____________.
[]
null
238
Class $$\matrix{ {{{10}^{th}}} &amp; {{{11}^{th}}} &amp; {{{12}^{th}}} \cr } $$<br><br>Total student $$\matrix{ 5 &amp; 6 &amp; 8 \cr } $$<br><br>$$\matrix{ 2 &amp; 3 &amp; 5 \cr } \Rightarrow $$ $${}^5{C_2} \times {}^6{C_3} \times {}^8{C_5}$$<br><br>Number of selection $$\matrix{ 2 &amp; 2 &am...
integer
jee-main-2021-online-25th-july-morning-shift
7,383
1ktgp4gdp
maths
permutations-and-combinations
conditional-combinations
Let S = {1, 2, 3, 4, 5, 6, 9}. Then the number of elements in the set T = {A $$ \subseteq $$ S : A $$\ne$$ $$\phi$$ and the sum of all the elements of A is not a multiple of 3} is _______________.
[]
null
80
3n type $$\to$$ 3, 6, 9 = P<br><br>3n $$-$$ 1 type $$\to$$ 2, 5 = Q<br><br>3n $$-$$ 2 type $$\to$$ 1, 4 = R<br><br>number of subset of S containing one element which are not divisible by 3 = $${}^2$$C<sub>1</sub> + $${}^2$$C<sub>1</sub> = 4<br><br>number of subset of S containing two numbers whose some is not divisible...
integer
jee-main-2021-online-27th-august-evening-shift
7,384
1l56rx9ym
maths
permutations-and-combinations
conditional-combinations
<p>Let A be a matrix of order 2 $$\times$$ 2, whose entries are from the set {0, 1, 2, 3, 4, 5}. If the sum of all the entries of A is a prime number p, 2 &lt; p &lt; 8, then the number of such matrices A is ___________.</p>
[]
null
180
<p>$$\because$$ Sum of all entries of matrix A must be prime p such that 2 < p < 8 then sum of entries may be 3, 5 or 7.</p> <p>If sum is 3 then possible entries are (0, 0, 0, 3), (0, 0, 1, 2) or (0, 1, 1, 1).</p> <p>$$\therefore$$ Total number of matrices = 4 + 4 + 12 = 20</p> <p>If sum of 5 then possible entries are...
integer
jee-main-2022-online-27th-june-evening-shift
7,386
1l58afhi6
maths
permutations-and-combinations
conditional-combinations
<p>There are ten boys B<sub>1</sub>, B<sub>2</sub>, ......., B<sub>10</sub> and five girls G<sub>1</sub>, G<sub>2</sub>, ........, G<sub>5</sub> in a class. Then the number of ways of forming a group consisting of three boys and three girls, if both B<sub>1</sub> and B<sub>2</sub> together should not be the members of ...
[]
null
1120
<p>Number of ways when B<sub>1</sub> and B<sub>2</sub> are not together</p> <p>= Total number of ways of selecting 3 boys $$-$$ B<sub>1</sub> and B<sub>2</sub> are together</p> <p>= <sup>10</sup>C<sub>3</sub> $$-$$ <sup>8</sup>C<sub>1</sub></p> <p>= $${{10\,.\,9\,.\,8} \over {1\,.\,2\,.\,3}} - 8$$</p> <p>= 112</p> <p>N...
integer
jee-main-2022-online-26th-june-morning-shift
7,388
1l5c20i6d
maths
permutations-and-combinations
conditional-combinations
<p>In an examination, there are 5 multiple choice questions with 3 choices, out of which exactly one is correct. There are 3 marks for each correct answer, $$-$$2 marks for each wrong answer and 0 mark if the question is not attempted. Then, the number of ways a student appearing in the examination gets 5 marks is ____...
[]
null
40
Let student marks $x$ correct answers and $y$ incorrect. So <br/><br/> $3 x-2 y=5$ and $x+y \leq 5$ where $x, y \in \mathrm{W}$ <br/><br/> Only possible solution is $(x, y)=(3,2)$ <br/><br/> Students can mark correct answers by only one choice but for an incorrect answer, there are two choices. So total number of ways ...
integer
jee-main-2022-online-24th-june-morning-shift
7,390
ldqvb3cg
maths
permutations-and-combinations
conditional-combinations
The number of ways of selecting two numbers $a$ and $b, a \in\{2,4,6, \ldots ., 100\}$ and $b \in\{1,3,5, \ldots . ., 99\}$ such that 2 is the remainder when $a+b$ is divided by 23 is :
[{"identifier": "A", "content": "186"}, {"identifier": "B", "content": "54"}, {"identifier": "C", "content": "108"}, {"identifier": "D", "content": "268"}]
["C"]
null
<p>$$a+b=23\lambda+2$$</p> <p>$$\lambda=0,1,2,$$ ...., but $$\lambda$$ cannot be even as $$a+b$$ is odd</p> <p>$$\lambda=1$$ $$(a, b)\to12$$ pairs</p> <p>$$\lambda=3$$ $$(a,b)\to35$$ pairs</p> <p>$$\lambda=5$$ $$(a,b)\to42$$ pairs</p> <p>$$\lambda=7$$ $$(a,b)\to19$$ pairs</p> <p>$$\lambda=9$$ $$(a,b)\to0$$ pairs</p> <p...
mcq
jee-main-2023-online-30th-january-evening-shift
7,392
1ldu63yht
maths
permutations-and-combinations
conditional-combinations
<p>Suppose Anil's mother wants to give 5 whole fruits to Anil from a basket of 7 red apples, 5 white apples and 8 oranges. If in the selected 5 fruits, at least 2 oranges, at least one red apple and at least one white apple must be given, then the number of ways, Anil's mother can offer 5 fruits to Anil is ____________...
[]
null
6860 OR 3
Total 8 oranges, 5 white apple and 7 red apple. 5 fruits needs to be selected. <br/><br/> <b>Case I</b>: 3 orange $+1$ red apple $+1$ white apple <br/><br/> $$ ={ }^{8} C_{3} \times{ }^{7} C_{1} \times{ }^{5} C_{1}=1960 $$ <br/><br/> <b>Case II</b> : 2 oranges $+2$ red apples $+1$ white apple. <br/><br/> $$ ={ }^{8} C_...
integer
jee-main-2023-online-25th-january-evening-shift
7,394
1ldwwxq9r
maths
permutations-and-combinations
conditional-combinations
<p>The number of square matrices of order 5 with entries from the set {0, 1}, such that the sum of all the elements in each row is 1 and the sum of all the elements in each column is also 1, is :</p>
[{"identifier": "A", "content": "125"}, {"identifier": "B", "content": "150"}, {"identifier": "C", "content": "225"}, {"identifier": "D", "content": "120"}]
["D"]
null
<p><img src="https://app-content.cdn.examgoal.net/fly/@width/image/1le5h0vkb/6ab5456d-64a1-4237-89f3-e400627057ab/241652a0-ad13-11ed-8a8c-4d67f5492755/file-1le5h0vkc.png?format=png" data-orsrc="https://app-content.cdn.examgoal.net/image/1le5h0vkb/6ab5456d-64a1-4237-89f3-e400627057ab/241652a0-ad13-11ed-8a8c-4d67f5492755...
mcq
jee-main-2023-online-24th-january-evening-shift
7,395
1ldyc2w6e
maths
permutations-and-combinations
conditional-combinations
<p>A boy needs to select five courses from 12 available courses, out of which 5 courses are language courses. If he can choose at most two language courses, then the number of ways he can choose five courses is __________</p>
[]
null
546
<p>Among 12 courses, 5 courses are of language.</p> <p>$$\therefore$$ Remaining 7 are different courses.</p> <p>Now, number of ways to select 5 courses where at most 2 language courses present.</p> <p><style type="text/css"> .tg {border-collapse:collapse;border-spacing:0;} .tg td{border-color:black;border-style:solid;...
integer
jee-main-2023-online-24th-january-morning-shift
7,396
1ldyc8xzj
maths
permutations-and-combinations
conditional-combinations
<p>The number of 9 digit numbers, that can be formed using all the digits of the number 123412341 so that the even digits occupy only even places, is ______________.</p>
[]
null
60
<p>Here, even digits are 2 and 4.</p> <p>Number of digit "2" presents = 2</p> <p>Number of digit "4" presents = 2</p> <p>$$\therefore$$ Total even digits = 4</p> <p><img src="https://app-content.cdn.examgoal.net/fly/@width/image/1le2pxjq6/e260bc6f-c1c6-485e-abbc-aa68e85a10dd/9fbb03e0-ab8f-11ed-a599-53c07234da0d/file-1l...
integer
jee-main-2023-online-24th-january-morning-shift
7,397
1lgq0urew
maths
permutations-and-combinations
conditional-combinations
<p>The number of seven digit positive integers formed using the digits $$1,2,3$$ and $$4$$ only and sum of the digits equal to $$12$$ is ___________.</p>
[]
null
413
$$ x_1+x_2+x_3+\ldots x_7=12 $$. This equation represents the number of ways to distribute 12 identical items (the sum of the digits) into 7 distinct boxes (the seven digits of the number), where each box can contain one of the numbers 1, 2, 3, or 4. <br/><br/>Number of solutions <br/><br/>$$ \begin{aligned} & =\text {...
integer
jee-main-2023-online-13th-april-morning-shift
7,398
1lguw0e0f
maths
permutations-and-combinations
conditional-combinations
<p>The number of triplets $$(x, \mathrm{y}, \mathrm{z})$$, where $$x, \mathrm{y}, \mathrm{z}$$ are distinct non negative integers satisfying $$x+y+z=15$$, is :</p>
[{"identifier": "A", "content": "136"}, {"identifier": "B", "content": "80"}, {"identifier": "C", "content": "92"}, {"identifier": "D", "content": "114"}]
["D"]
null
We have, $x+y+z=15$ <br/><br/>$$ \begin{aligned} \text { Total number of solution } & ={ }^{15+3-1} C_{3-1} \\\\ & ={ }^{17} C_2=\frac{17 \times 16}{1 \times 2}=136 \end{aligned} $$ <br/><br/>Now, we need to exclude the solutions where two of $(x, y, z)$ are the same. <br/><br/>1) For the case $x = y \neq z$ : <br/><b...
mcq
jee-main-2023-online-11th-april-morning-shift
7,399
1lh245n1s
maths
permutations-and-combinations
conditional-combinations
<p>The number of ways of giving 20 distinct oranges to 3 children such that each child gets at least one orange is ___________.</p>
[]
null
3483638676
<li><p><strong>Total ways without any restrictions :</strong> <br/><br/>There are $3^{20}$ ways to distribute the oranges to the 3 children.</p> </li> <li><p><strong>Number of ways one child receives no orange :</strong> <br/><br/>Choose 1 child out of the 3 to not receive any orange in ${ }^3 C_1 = 3$ ways. Distribute...
integer
jee-main-2023-online-6th-april-morning-shift
7,400
jaoe38c1lsd39r8j
maths
permutations-and-combinations
conditional-combinations
<p>The number of ways in which 21 identical apples can be distributed among three children such that each child gets at least 2 apples, is</p>
[{"identifier": "A", "content": "130"}, {"identifier": "B", "content": "136"}, {"identifier": "C", "content": "142"}, {"identifier": "D", "content": "406"}]
["B"]
null
<p>To solve this problem, we can use a classic combinatorics method known as "stars and bars" (or "balls and bins"), which is a way to solve problems involving distributing identical items into distinct groups with certain restrictions.</p> <p>First, since each child must get at least 2 apples, let's give 2 apples to ...
mcq
jee-main-2024-online-31st-january-evening-shift
7,401
lv3ve4dd
maths
permutations-and-combinations
conditional-combinations
<p>The number of ways five alphabets can be chosen from the alphabets of the word MATHEMATICS, where the chosen alphabets are not necessarily distinct, is equal to:</p>
[{"identifier": "A", "content": "179"}, {"identifier": "B", "content": "177"}, {"identifier": "C", "content": "175"}, {"identifier": "D", "content": "181"}]
["A"]
null
<p>$$\begin{aligned} & 2 M \\ & 2 A \\ & 2 T \\ & H, E, I, C, S \end{aligned}$$</p> <p>Case-I</p> <p>2 Alike 2 Alike 1 Diff</p> <p>$${ }^3 C_2 \times{ }^6 C_1=18$$</p> <p>Case-II</p> <p>2 Alike + 3 Diff</p> <p>$${ }^3 C_1 \times{ }^7 C_3=105$$</p> <p>Case-III</p> <p>All different</p> <p>$${ }^8 C_5=56$$</p> <p>Total wa...
mcq
jee-main-2024-online-8th-april-evening-shift
7,403
TIV9ByukNGgS1zIC
maths
permutations-and-combinations
conditional-permutations
Number greater than 1000 but less than 4000 is formed using the digits 0, 1, 2, 3, 4 (repetition allowed). Their number is :
[{"identifier": "A", "content": "125"}, {"identifier": "B", "content": "105"}, {"identifier": "C", "content": "374"}, {"identifier": "D", "content": "625"}]
["C"]
null
There are 3 possible ways that we can make number greater than 1000 but less than 4000 using the digits 0, 1, 2, 3, 4 where repetition is allowed <br><br><b>Case 1 :</b> First digit is 1 = 1 _ _ _ <br><br>Possible numbers starting with 1 = 1$$ \times $$5$$ \times $$5$$ \times $$5 = 125 <br><br>But this includes 1000 al...
mcq
aieee-2002
7,404
e1EyFwNJvi8vSFaE
maths
permutations-and-combinations
conditional-permutations
Total number of four digit odd numbers that can be formed using 0, 1, 2, 3, 5, 7 (using repetition allowed) are :
[{"identifier": "A", "content": "216"}, {"identifier": "B", "content": "375"}, {"identifier": "C", "content": "400"}, {"identifier": "D", "content": "720"}]
["D"]
null
<img class="question-image" src="https://res.cloudinary.com/dckxllbjy/image/upload/v1734263746/exam_images/x99fiwum87l1tzmfgxkv.webp" loading="lazy" alt="AIEEE 2002 Mathematics - Permutations and Combinations Question 177 English Explanation"> <br>$$\therefore$$ Total no of ways = 5$$ \times $$6$$ \times $$6$$ \times $...
mcq
aieee-2002
7,405
n1oWTwJqCyxG22uT
maths
permutations-and-combinations
conditional-permutations
How many ways are there to arrange the letters in the word GARDEN with vowels in alphabetical order
[{"identifier": "A", "content": "480"}, {"identifier": "B", "content": "240"}, {"identifier": "C", "content": "360"}, {"identifier": "D", "content": "120"}]
["C"]
null
In the word ''GARDEN'', there are two vowels A and E present, and A should come always before E. <br><br>$$\therefore\,\,\,$$ Total no of ways = $${{6!} \over {2!}}$$ = 360 <br><br>Here A and E has fixed order that is why we divide by 2!.
mcq
aieee-2004
7,407
CtCfGCORzMr3qyUf
maths
permutations-and-combinations
conditional-permutations
How many different words can be formed by jumbling the letters in the word MISSISSIPPI in which no two S are adjacent?
[{"identifier": "A", "content": "$$8.{}^6{C_4}.{}^7{C_4}$$ "}, {"identifier": "B", "content": "$$6.7.{}^8{C_4}$$ "}, {"identifier": "C", "content": "$$6.8.{}^7{C_4}$$. "}, {"identifier": "D", "content": "$$7.{}^6{C_4}.{}^8{C_4}$$ "}]
["D"]
null
<p>This problem is solved using gap method. As here no 'S' is adjacent to each other so we have to put them in the gap. So first write all the letters other than 'S' such a way that there is a gap between two letters.</p> <p>Given word is MISSISSIPPI.</p> <p>Here, I = 4 times, S = 4 times, P = 2 times, M = 1 time</p> <...
mcq
aieee-2008
7,408
pOakikkdQhU84tLNpvMvZ
maths
permutations-and-combinations
conditional-permutations
If the four letter words (need not be meaningful ) are to be formed using the letters from the word “MEDITERRANEAN” such that the first letter is R and the fourth letter is E, then the total number of all such words is :
[{"identifier": "A", "content": "$${{11!} \\over {{{\\left( {2!} \\right)}^3}}}$$"}, {"identifier": "B", "content": "110"}, {"identifier": "C", "content": "56"}, {"identifier": "D", "content": "59"}]
["D"]
null
Here total no of different letters present are, <br><br>(1)&nbsp;&nbsp;&nbsp;One M <br><br>(2)&nbsp;&nbsp;&nbsp;Three E (E E E) <br><br>(3)&nbsp;&nbsp;&nbsp;One D <br><br>(4)&nbsp;&nbsp;&nbsp;One I <br><br>(5)&nbsp;&nbsp;&nbsp;One T <br><br>(6)&nbsp;&nbsp;&nbsp;Two R (R R) <br><br>(7)&nbsp;&nbsp;&nbsp;Two A (A A) <br><...
mcq
jee-main-2016-online-9th-april-morning-slot
7,409
va6hXgEJsJa8x7wVuocWG
maths
permutations-and-combinations
conditional-permutations
The number of natural numbers less than 7,000 which can be formed by using the digits 0, 1, 3, 7, 9 (repitition of digits allowed) is equal to :
[{"identifier": "A", "content": "374"}, {"identifier": "B", "content": "372"}, {"identifier": "C", "content": "375"}, {"identifier": "D", "content": "250"}]
["A"]
null
Total no 1 digit numbers possible = 4 (allowed digits 1, 3, 7, 9) <br><br>Total no 2 digit numbers possible = 4$$ \times $$5 = 20 <br><br>Total no 3 digit numbers possible = 4$$ \times $$5$$ \times $$5 = 100 <br><br>Total no 4 digit numbers possible = 2$$ \times $$5$$ \times $$5$$ \times $$5 = 250 <br><br>So the number...
mcq
jee-main-2019-online-9th-january-evening-slot
7,410
VyKFCxCKFLUFzxl6WeXIp
maths
permutations-and-combinations
conditional-permutations
All possible numbers are formed using the digits 1, 1, 2, 2, 2, 2, 3, 4, 4 taken all at a time. The number of such numbers in which the odd digits occupy even places is :
[{"identifier": "A", "content": "175"}, {"identifier": "B", "content": "162"}, {"identifier": "C", "content": "160"}, {"identifier": "D", "content": "180"}]
["D"]
null
<picture><source media="(max-width: 320px)" srcset="https://res.cloudinary.com/dckxllbjy/image/upload/v1734266512/exam_images/lapq8as1rpgqmd4kignb.webp"><source media="(max-width: 500px)" srcset="https://res.cloudinary.com/dckxllbjy/image/upload/v1734267401/exam_images/ckx4aga8bpukg4jpltqh.webp"><source media="(max-wid...
mcq
jee-main-2019-online-8th-april-morning-slot
7,411
QpyXMtfVkQTUnuxoZ3qaz
maths
permutations-and-combinations
conditional-permutations
The number of four-digit numbers strictly greater than 4321 that can be formed using the digits 0,1,2,3,4,5 (repetition of digits is allowed) is :
[{"identifier": "A", "content": "306"}, {"identifier": "B", "content": "288"}, {"identifier": "C", "content": "310"}, {"identifier": "D", "content": "360"}]
["C"]
null
<picture><source media="(max-width: 320px)" srcset="https://res.cloudinary.com/dckxllbjy/image/upload/v1734263995/exam_images/sztfmutoowxk1xy02qdm.webp"><source media="(max-width: 500px)" srcset="https://res.cloudinary.com/dckxllbjy/image/upload/v1734265675/exam_images/gagx61scdkiyqg7gijyq.webp"><source media="(max-wid...
mcq
jee-main-2019-online-8th-april-evening-slot
7,412
T7pubLMDX4L70jGUBQ3rsa0w2w9jwy0oxdn
maths
permutations-and-combinations
conditional-permutations
The number of 6 digit numbers that can be formed using the digits 0, 1, 2, 5, 7 and 9 which are divisible by 11 and no digit is repeated is :
[{"identifier": "A", "content": "36"}, {"identifier": "B", "content": "60"}, {"identifier": "C", "content": "72"}, {"identifier": "D", "content": "48"}]
["B"]
null
<picture><source media="(max-width: 320px)" srcset="https://res.cloudinary.com/dckxllbjy/image/upload/v1734267428/exam_images/uaonbq0dqm3qxf5khxpq.webp"><source media="(max-width: 500px)" srcset="https://res.cloudinary.com/dckxllbjy/image/upload/v1734265874/exam_images/qiafu8cvzerixiwxgsev.webp"><source media="(max-wid...
mcq
jee-main-2019-online-10th-april-morning-slot
7,413
E0UshBABGmQdzdNVQPjgy2xukg4n2d68
maths
permutations-and-combinations
conditional-permutations
The number of words (with or without meaning) that can be formed from all the letters of the word “LETTER” in which vowels never come together is ________ .
[]
null
120
Consonants $$ \to $$ LTTR <br>Vowels $$ \to $$ EE <br><br>Total No of words = $${{6!} \over {2!2!}}$$ = 180 <br><br>Total no of words if vowels are together <br>= $${{5!} \over {2!}}$$ = 60 <br><br>$$ \therefore $$ Total no of words where<br> vowels never come together = 180 – 60 = 120.
integer
jee-main-2020-online-6th-september-evening-slot
7,414
peQrKRXgQeisz7wOkTjgy2xukfuv9z75
maths
permutations-and-combinations
conditional-permutations
Two families with three members each and one family with four members are to be seated in a row. In how many ways can they be seated so that the same family members are not separated?
[{"identifier": "A", "content": "2! 3! 4!"}, {"identifier": "B", "content": "(3!)<sup>3</sup>.(4!) "}, {"identifier": "C", "content": "3! (4!)<sup>3</sup>"}, {"identifier": "D", "content": "(3!)<sup>2</sup>.(4!)"}]
["B"]
null
F<sub>1</sub> $$ \to $$ 3 members <br>F<sub>2</sub> $$ \to $$ 3 members <br>F<sub>3</sub> $$ \to $$ 4 members <br><br>Total arrangements of three families = 3! <br><br>Arrangement between members of F<sub>1</sub> family = 3! <br><br>Arrangement between members of F<sub>2</sub> family = 3! <br><br>Arrangement between me...
mcq
jee-main-2020-online-6th-september-morning-slot
7,415
C8HGleU1NgkvV0IfgIjgy2xukfjjwd85
maths
permutations-and-combinations
conditional-permutations
The number of words, with or without meaning, that can be formed by taking 4 letters at a time from the letters of the word ’SYLLABUS’ such that two letters are distinct and two letters are alike, is :
[]
null
240
In 'SYLLABUS' word <br><br>1. Two S letters <br><br>2. Two L letters <br><br>3. One Y letter <br><br>4. One A letter <br><br>5. One B letter <br><br>6. One U letter <br><br>Number of ways we can select two alike letters = <sup>2</sup>C<sub>1</sub> <br><br>Then number of ways we can select two distinct letters = <sup>5<...
integer
jee-main-2020-online-5th-september-morning-slot
7,416
FnMRlmZon3hFFMIfYv7k9k2k5ior0st
maths
permutations-and-combinations
conditional-permutations
If the number of five digit numbers with distinct digits and 2 at the 10<sup>th</sup> place is 336 k, then k is equal to :
[{"identifier": "A", "content": "6"}, {"identifier": "B", "content": "8"}, {"identifier": "C", "content": "4"}, {"identifier": "D", "content": "7"}]
["B"]
null
<img src="https://res.cloudinary.com/dckxllbjy/image/upload/v1734265718/exam_images/p2ps2ybooqoc7gyxtqdc.webp" style="max-width: 100%;height: auto;display: block;margin: 0 auto;" loading="lazy" alt="JEE Main 2020 (Online) 9th January Morning Slot Mathematics - Permutations and Combinations Question 126 English Explanat...
mcq
jee-main-2020-online-9th-january-morning-slot
7,417
IGIb0SRhLxdVea31gf1kls5ho0j
maths
permutations-and-combinations
conditional-permutations
The total number of numbers, lying between 100 and 1000 that can be formed with the digits 1, 2, 3, 4, 5, if the repetition of digits is not allowed and numbers are divisible by either 3 or 5, is _____________.
[]
null
32
The numbers are lying between 100 and 1000 then each number is of three digits. <br><br>The possible combination of 3 digits numbers are <br><br>1, 2, 3; 1, 2, 4; 1, 2, 5; 1, 3, 4; 1, 3, 5; 1, 4, 5; 2, 3, 4; 2, 3, 5; 2, 4, 5; and 3, 4, 5. <br><br>The possible combination of numbers which are divisible by 3 are 1, 2, 3;...
integer
jee-main-2021-online-25th-february-morning-slot
7,418
vTTgxkoqnfAoseQRCc1kmlj9jej
maths
permutations-and-combinations
conditional-permutations
The number of times the digit 3 will be written when listing the integers from 1 to 1000 is :
[]
null
300
In single digit numbers = 1 <br><br>In double digit numbers = 10 + 9 = 19 <br><br>In triple digit numbers = 100 + 90 + 90 = 280 <br><br>Total = 300 times
integer
jee-main-2021-online-18th-march-morning-shift
7,420
1kruajm92
maths
permutations-and-combinations
conditional-permutations
If the digits are not allowed to repeat in any number formed by using the digits 0, 2, 4, 6, 8, then the number of all numbers greater than 10,000 is equal to _____________.
[]
null
96
<img src="https://res.cloudinary.com/dckxllbjy/image/upload/v1734264389/exam_images/aiakh8f4ehgt1n8uagk2.webp" style="max-width: 100%;height: auto;display: block;margin: 0 auto;" loading="lazy" alt="JEE Main 2021 (Online) 22th July Evening Shift Mathematics - Permutations and Combinations Question 100 English Explanati...
integer
jee-main-2021-online-22th-july-evening-shift
7,421
1ktbiwpdb
maths
permutations-and-combinations
conditional-permutations
The number of three-digit even numbers, formed by the digits 0, 1, 3, 4, 6, 7 if the repetition of digits is not allowed, is ______________.
[]
null
52
(i) When '0' is at unit place<br><br><img src="https://res.cloudinary.com/dckxllbjy/image/upload/v1734264026/exam_images/psga0gi4ukcamvr6fhaw.webp" style="max-width: 100%;height: auto;display: block;margin: 0 auto;" loading="lazy" alt="JEE Main 2021 (Online) 26th August Morning Shift Mathematics - Permutations and Comb...
integer
jee-main-2021-online-26th-august-morning-shift
7,422
1kteplg92
maths
permutations-and-combinations
conditional-permutations
A number is called a palindrome if it reads the same backward as well as forward. For example 285582 is a six digit palindrome. The number of six digit palindromes, which are divisible by 55, is ____________.
[]
null
100
<table class="tg"> <thead> <tr> <td class="tg-baqh">5</td> <td class="tg-baqh">a</td> <td class="tg-baqh">b</td> <td class="tg-baqh">b</td> <td class="tg-baqh">a</td> <td class="tg-baqh">5</td> </tr> </thead> </table> <br><br>For divisible by 55 it shall be divisible by 11 and 5 both, for di...
integer
jee-main-2021-online-27th-august-morning-shift
7,423
1ktobhmqv
maths
permutations-and-combinations
conditional-permutations
All the arrangements, with or without meaning, of the word FARMER are written excluding any word that has two R appearing together. The arrangements are listed serially in the alphabetic order as in the English dictionary. Then the serial number of the word FARMER in this list is ___________.
[]
null
77
First find all possible words and then subtract words from each case that have both R together. <br><br>FARMER (6)<br><br>A, E, F, M, R, R<br><br><style type="text/css"> .tg {border-collapse:collapse;border-spacing:0;width:100%} .tg td{border-color:black;border-style:solid;border-width:1px;font-family:Arial, sans-seri...
integer
jee-main-2021-online-1st-september-evening-shift
7,425
1l546nn3x
maths
permutations-and-combinations
conditional-permutations
<p>Let b<sub>1</sub>b<sub>2</sub>b<sub>3</sub>b<sub>4</sub> be a 4-element permutation with b<sub>i</sub> $$\in$$ {1, 2, 3, ........, 100} for 1 $$\le$$ i $$\le$$ 4 and b<sub>i</sub> $$\ne$$ b<sub>j</sub> for i $$\ne$$ j, such that either b<sub>1</sub>, b<sub>2</sub>, b<sub>3</sub> are consecutive integers or b<sub>2</...
[]
null
18915
<p>There are 98 sets of three consecutive integer and 97 sets of four consecutive integers.</p> <p>Using the principle of inclusion and exclusion,</p> <p>Number of permutations of $b_{1} b_{2} b_{3} b_{4}=$ Number of permutations when $b_{1} b_{2} b_{3}$ are consecutive + Number of permutations when $b_{2} b_{3} b_{4}$...
integer
jee-main-2022-online-29th-june-morning-shift
7,426
1l54udtan
maths
permutations-and-combinations
conditional-permutations
<p>The total number of four digit numbers such that each of first three digits is divisible by the last digit, is equal to ____________.</p>
[]
null
1086
If unit digit is 1 then $\rightarrow 9 \times$ s $10 \times 10=900$ numbers <br/><br/>If unit digit is 2 then $\rightarrow 4 \times 5 \times 5=100$ numbers <br/><br/>If unit digit is 3 then $\rightarrow 3 \times 4 \times 4=48$ numbers<br/><br/> If unit digit is 4 then $\rightarrow 2 \times 3 \times 3=18$ numbers<br/><b...
integer
jee-main-2022-online-29th-june-evening-shift
7,427
1l5668ose
maths
permutations-and-combinations
conditional-permutations
<p>The total number of 5-digit numbers, formed by using the digits 1, 2, 3, 5, 6, 7 without repetition, which are multiple of 6, is :</p>
[{"identifier": "A", "content": "36"}, {"identifier": "B", "content": "48"}, {"identifier": "C", "content": "60"}, {"identifier": "D", "content": "72"}]
["D"]
null
To make a no. divisible by 3 we can use the digits 1,2,5,6,7 or 1,2,3,5,7.<br/><br/> Using 1,2,5,6,7, number of even numbers is = 4 × 3 × 2 × 1 × 2 = 48<br/><br/> Using 1,2,3,5,7, number of even numbers is = 4 × 3 × 2 × 1 × 1 = 24<br/><br/> Required answer is 72.
mcq
jee-main-2022-online-28th-june-morning-shift
7,428
1l59le9dg
maths
permutations-and-combinations
conditional-permutations
<p>The total number of three-digit numbers, with one digit repeated exactly two times, is ______________.</p>
[]
null
243
<p>$$C - 1:$$ All digits are non-zero</p> <p>$${}^9{C_2}\,.\,2\,.\,{{3!} \over 2} = 216$$</p> <p>$$C - 2$$ : One digit is 0</p> <p>$$0,\,0,\,x \Rightarrow {}^9{C_1}\,.\,1 = 9$$</p> <p>$$0,x,\,x \Rightarrow {}^9{C_1}\,.\,2 = 18$$</p> <p>Total $$ = 216 + 27 = 243$$</p>
integer
jee-main-2022-online-25th-june-evening-shift
7,429
1l5ajmbj0
maths
permutations-and-combinations
conditional-permutations
<p>The number of 3-digit odd numbers, whose sum of digits is a multiple of 7, is _____________.</p>
[]
null
63
For odd number unit place shall be $1,3,5,7$ or 9 .<br/><br/> $\therefore$ x y 1, x y 3, x y 5, x y 7, x y 9 are the type of numbers. numbers.<br/><br/> If $x \,y\, 1$ then $x+y=6,13,20$... Cases are required<br/><br/> i.e., $6+6+0+\ldots=12$ ways<br/><br/> If $x \, y \,3$ then<br/><br/> $x+y=4,11,18, \ldots$ Cases are...
integer
jee-main-2022-online-25th-june-morning-shift
7,430
1l5bb1vut
maths
permutations-and-combinations
conditional-permutations
<p>The number of 7-digit numbers which are multiples of 11 and are formed using all the digits 1, 2, 3, 4, 5, 7 and 9 is _____________.</p>
[]
null
576
Digits are $1,2,3,4,5,7,9$<br/><br/> Multiple of $11 \rightarrow$ Difference of sum at even and odd place is divisible by 11 .<br/><br/> Let number of the form <b>abcdefg</b><br/><br/> $$ \begin{aligned} &\therefore(\mathrm{a}+\mathrm{c}+\mathrm{e}+\mathrm{g})-(\mathrm{b}+\mathrm{d}+\mathrm{f})=11 \mathrm{x} \\\\ &\mat...
integer
jee-main-2022-online-24th-june-evening-shift
7,431
1l5w0pg9y
maths
permutations-and-combinations
conditional-permutations
<p>The number of 6-digit numbers made by using the digits 1, 2, 3, 4, 5, 6, 7, without repetition and which are multiple of 15 is ____________.</p>
[]
null
360
<p>A number is multiple of 15 when the number is divisible by 5 and sum of digits of the number is divisible by 3.</p> <p><img src="https://app-content.cdn.examgoal.net/fly/@width/image/1l65uqr2z/3aa8732e-2bc7-4c8a-a45b-f53f925f4291/0f4fb6b0-0ee7-11ed-a7de-eff776fdb55c/file-1l65uqr30.png?format=png" data-orsrc="https:/...
integer
jee-main-2022-online-30th-june-morning-shift
7,432
1l6gjaknm
maths
permutations-and-combinations
conditional-permutations
<p>The number of 5-digit natural numbers, such that the product of their digits is 36 , is __________.</p>
[]
null
180
<p>Factors of 36 = 2<sup>2</sup> . 3<sup>2</sup> . 1</p> <p>Five-digit combinations can be</p> <p>(1, 2, 2, 3, 3) (1, 4, 3, 3, 1), (1, 9, 2, 2, 1)</p> <p>(1, 4, 9, 11) (1, 2, 3, 6, 1) (1, 6, 6, 1, 1)</p> <p>i.e., total numbers</p> <p>$${{5!} \over {2!2!}} + {{5!} \over {2!2!}} + {{5!} \over {2!2!}} + {{5!} \over {3!}} ...
integer
jee-main-2022-online-26th-july-morning-shift
7,433
1l6hzoa3g
maths
permutations-and-combinations
conditional-permutations
<p>Numbers are to be formed between 1000 and 3000 , which are divisible by 4 , using the digits $$1,2,3,4,5$$ and 6 without repetition of digits. Then the total number of such numbers is ____________.</p>
[]
null
30
Here 1<sup>st</sup> digit is 1 or 2 only<br><br> <b>Case-I</b><br><br> If first digit is 1<br><br> Then last two digits can be 24, 32, 36, 52, 56, 64 <br><br> <img src="https://app-content.cdn.examgoal.net/fly/@width/image/1l97twac2/f9689a1f-abde-44d3-bf0b-1a1289bdd7bc/f788ec10-4b61-11ed-80b9-4154b7faa509/file-1l97twac...
integer
jee-main-2022-online-26th-july-evening-shift
7,434
1ldptkt5n
maths
permutations-and-combinations
conditional-permutations
<p>Number of 4-digit numbers that are less than or equal to 2800 and either divisible by 3 or by 11 , is equal to ____________.</p>
[]
null
710
Numbers which are divisible by 3 (4 digit) and less than or equal to 2800 <br/><br/>$=\frac{2799-1002}{3}+1=600$ <br/><br/>Numbers which are divisible by 11 (4 digit) and less than or equal to 2800 <br/><br/>$=\frac{2794-1001}{11}+1=164$ <br/><br/>Numbers which are divisible by 33 (4 digit) and less than or equal t...
integer
jee-main-2023-online-31st-january-morning-shift
7,438
ldqzur7j
maths
permutations-and-combinations
conditional-permutations
The number of seven digits odd numbers, that can be formed using all the<br/><br/>seven digits 1, 2, 2, 2, 3, 3, 5 is ____________.
[]
null
240
<p>$$.......1 \to {{6!} \over {2!3!}} = 60$$</p> <p>$$.......3 \to {{6!} \over {3!}} = 120$$</p> <p>$$.......5 \to {{6!} \over {3!2!}} = 60$$</p> <p>Total = 240</p>
integer
jee-main-2023-online-30th-january-evening-shift
7,439
1ldr7rs32
maths
permutations-and-combinations
conditional-permutations
<p>Number of 4-digit numbers (the repetition of digits is allowed) which are made using the digits 1, 2, 3 and 5, and are divisible by 15, is equal to ___________.</p>
[]
null
21
<p>We have to make 4 digit numbers using the digits, 1, 2, 3 and 5. <br><br>The unit digit of the 4 digit number will be 5.</p> <p><img src="https://app-content.cdn.examgoal.net/fly/@width/image/1lf61sqp4/9a9d5f7b-a4f5-43a8-8dd7-0303f78b9d4c/98f24a80-c130-11ed-8b61-5f07d5ca97fb/file-1lf61sqp5.png?format=png" data-orsrc...
integer
jee-main-2023-online-30th-january-morning-shift
7,440
1ldswvvgd
maths
permutations-and-combinations
conditional-permutations
<p>If all the six digit numbers $$x_1\,x_2\,x_3\,x_4\,x_5\,x_6$$ with $$0&lt; x_1 &lt; x_2 &lt; x_3 &lt; x_4 &lt; x_5 &lt; x_6$$ are arranged in the increasing order, then the sum of the digits in the $$\mathrm{72^{th}}$$ number is _____________.</p>
[]
null
32
$1 \ldots \ldots \ldots \ldots \ldots \rightarrow{ }^{8} C_{5}=56$ <br/><br/> 23 $\ldots\ldots\ldots\ldots\ldots\rightarrow{ }^{6} C_{4}=\frac{15}{71}$ <br/><br/> $72^{\text {th }}$ number $=245678$ <br/><br/> Sum $=32$
integer
jee-main-2023-online-29th-january-morning-shift
7,441
1ldu5hsr5
maths
permutations-and-combinations
conditional-permutations
<p>The number of numbers, strictly between 5000 and 10000 can be formed using the digits 1, 3, 5, 7, 9 without repetition, is :</p>
[{"identifier": "A", "content": "120"}, {"identifier": "B", "content": "6"}, {"identifier": "C", "content": "72"}, {"identifier": "D", "content": "12"}]
["C"]
null
Numbers between 5000 &amp; 10000<br><br> Using digits 1, 3, 5, 7, 9<br><br> <img src="https://app-content.cdn.examgoal.net/fly/@width/image/1lef5alut/f8dc7152-4573-493d-a2cc-0b09243a1255/1b9fc550-b265-11ed-a126-5dfa1a9d5fb8/file-1lef5aluu.png?format=png" data-orsrc="https://app-content.cdn.examgoal.net/image/1lef5alut/...
mcq
jee-main-2023-online-25th-january-evening-shift
7,442
lgnys0w5
maths
permutations-and-combinations
conditional-permutations
A person forgets his 4-digit ATM pin code. But he remembers that in the code all the digits are different, the greatest digit is 7 and the sum of the first two digits is equal to the sum of the last two digits. Then the maximum number of trials necessary to obtain the correct code is ___________.
[]
null
72
Let the 4-digit ATM pin code be represented by the digits $$abxy$$, where all digits are different, the greatest digit is 7, and the sum of the first two digits is equal to the sum of the last two digits: $$a + b = x + y$$. <br><br>Since the greatest digit is 7, the possible digits for the pin code are $$0, 1, 2, 3, 4...
integer
jee-main-2023-online-15th-april-morning-shift
7,444
1lgrefqkf
maths
permutations-and-combinations
conditional-permutations
<p>The number of five digit numbers, greater than 40000 and divisible by 5 , which can be formed using the digits $$0,1,3,5,7$$ and 9 without repetition, is equal to :</p>
[{"identifier": "A", "content": "132"}, {"identifier": "B", "content": "72"}, {"identifier": "C", "content": "120"}, {"identifier": "D", "content": "96"}]
["C"]
null
Since the five-digit number must be greater than 40000, the only options for the first digit are 5, 7, or 9. That leaves 3 remaining choices for the first digit. <br/><br/>Since the number has to be divisible by 5, the last digit must be 0 or 5. If the first digit is 5, the last digit can only be 0, since digits cann...
mcq
jee-main-2023-online-12th-april-morning-shift
7,446
1lgrgicm5
maths
permutations-and-combinations
conditional-permutations
<p>Let the digits a, b, c be in A. P. Nine-digit numbers are to be formed using each of these three digits thrice such that three consecutive digits are in A.P. at least once. How many such numbers can be formed?</p>
[]
null
1260
<p>The problem involves forming nine-digit numbers from three digits a, b, c which are in Arithmetic Progression (AP), used three times each, such that at least once, three consecutive digits are in AP.</p> <p>We have the two possible sequences for the AP :</p> <ol> <li>a, b, c</li> <li>c, b, a</li> </ol> <p>This shows...
integer
jee-main-2023-online-12th-april-morning-shift
7,447
1lgxwdlm3
maths
permutations-and-combinations
conditional-permutations
<p>The number of permutations, of the digits 1, 2, 3, ..., 7 without repetition, which neither contain the string 153 nor the string 2467, is ___________.</p>
[]
null
4898
Given that digits are $1,2,3,4,5,6,7$ <br/><br/>Total permutations $=7$! <br/><br/>Let $p=$ Number which containing string 153 <br/><br/>$q=$ Number which containing string 2467 <br/><br/>$$ \begin{array}{ll} & \therefore n(p)=5! \times 1 \\\\ & \Rightarrow n(q)=4! \times 1 \\\\ & \Rightarrow n(p \cap q)=2! \end{array}...
integer
jee-main-2023-online-10th-april-morning-shift
7,448
1lgzxfup5
maths
permutations-and-combinations
conditional-permutations
<p>The number of arrangements of the letters of the word "INDEPENDENCE" in which all the vowels always occur together is :</p>
[{"identifier": "A", "content": "16800"}, {"identifier": "B", "content": "14800"}, {"identifier": "C", "content": "18000"}, {"identifier": "D", "content": "33600"}]
["A"]
null
In the given word, <br/><br/>vowels are : I, E, E, E, E <br/><br/>Consonants are : N, D, P, N, D, N, C <br/><br/>So, number of words $=\frac{8 !}{3 ! 2 !} \times \frac{5 !}{4 !}$ <br/><br/>$=\frac{8 \times 7 \times 6 \times 5 \times 4}{2} \times 5=16800$ <br/><br/><b>Concept :</b> <br/><br/>Out of $n$ objects, if $r$ t...
mcq
jee-main-2023-online-8th-april-morning-shift
7,450
1lh2yrfzn
maths
permutations-and-combinations
conditional-permutations
<p>The number of 4-letter words, with or without meaning, each consisting of 2 vowels and 2 consonants, which can be formed from the letters of the word UNIVERSE without repetition is __________.</p>
[]
null
432
Given, word is UNIVERSE <br/><br/>Here, vowels are E, I, U and consonants are N, R, S, V <br/><br/>$\therefore$ Required number of 4-letters words, with or without meaning, <br/><br/>each consisting of 2 vowels and 2 consonants <br/><br/>$$ \begin{aligned} & ={ }^3 C_2 \times{ }^4 C_2 \times 4 ! \\\\ & ={ }^3 C_1 \t...
integer
jee-main-2023-online-6th-april-evening-shift
7,451
1lguwuo8m
maths
permutations-and-combinations
dearrangement
<p>In an examination, 5 students have been allotted their seats as per their roll numbers. The number of ways, in which none of the students sits on the allotted seat, is _________.</p>
[]
null
44
This problem can be solved using the concept of derangements, which is a permutation of objects where no object appears in its original position. In this case, we have 5 students who should not sit in their allotted seats. <br/><br/>The formula for calculating the number of derangements (also known as subfactorials) ...
integer
jee-main-2023-online-11th-april-morning-shift
7,452
38m7NMVKw7MZYgve
maths
permutations-and-combinations
divisibility-of-numbers
The sum of integers from 1 to 100 that are divisible by 2 or 5 is :
[{"identifier": "A", "content": "3000"}, {"identifier": "B", "content": "3050"}, {"identifier": "C", "content": "3600"}, {"identifier": "D", "content": "3250"}]
["B"]
null
According to this question, any number between 1 to 100 should be divisible by 2 or 5 but not by 2$$ \times $$5 = 10. <br><br>Possible numbers between 1 to 100 divisible by 2 are 2, 4, 6, .... , 100 <br><br>This is an A.P where first term = 2, last term = 100 and total terms = 50. <br><br>$$ \therefore $$ Sum of the nu...
mcq
aieee-2002
7,453