def calculate_tax(income, tax_brackets):
    """Calculate tax using progressive brackets."""
    tax = 0
    previous_limit = 0

    for bracket in sorted(tax_brackets, key=lambda x: x["limit"]):
        if income > bracket["limit"]:
            taxable_amount = bracket["limit"] - previous_limit
            tax += taxable_amount * bracket["rate"]
            previous_limit = bracket["limit"]
        else:
            tax += (income - previous_limit) * bracket["rate"]
            break
    return tax