Question:medium

The volume of a right circular cone is 1232 cm³ and its height is 14 cm. Find the radius of the base $(use \pi = 22/7)$.

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When evaluating fractions involving $\pi = \frac{22}{7}$, look closely at numbers to see if they are multiples of 7 or 11. If a value gives you an imperfect square like 84, check if a digit like 24 was misread as 14 during typesetting!
Updated On: May 30, 2026
  • 7 cm
  • 14 cm
  • 21 cm
  • 28 cm
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The Correct Option is A

Solution and Explanation

Step 1 : Understanding the Question:
This problem focuses on the geometric properties of a right circular cone, which is a three-dimensional shape with a circular base and a single vertex. The volume of such a shape represents the total space enclosed within its boundaries. In this specific scenario, we are provided with the total volume (capacity) and the perpendicular height of the cone. Our objective is to determine the radius of the base. Understanding the relationship between these dimensions is crucial, as the radius and height directly dictate the volume. We must use algebraic manipulation to isolate the radius variable and solve the equation.
Step 2 : Key Formulas and approach:
The fundamental formula used to calculate the volume ($V$) of a right circular cone is: $$V = \frac{1}{3}\pi r^2 h$$ Where:
$V$ represents the Volume ($1232\text{ cm}^3$).

$r$ represents the radius of the circular base (unknown).

$h$ represents the vertical height ($14\text{ cm}$).

$\pi$ is taken as $\frac{22}{7}$.

The approach involves substituting the known values into this formula and solving for $r^2$, followed by finding the square root to get $r$.
Step 3 : Detailed Explanation:

Start by substituting the given values into the volume formula: $1232 = \frac{1}{3} \times \frac{22}{7} \times r^2 \times 14$.

Simplify the expression by dividing the height (14) by the denominator of pi (7): $14 \div 7 = 2$.

The equation now becomes: $1232 = \frac{1}{3} \times 22 \times r^2 \times 2$.

Multiply the constants together: $1232 = \frac{44}{3} \times r^2$.

To isolate $r^2$, multiply 1232 by 3 and divide by 44: $r^2 = \frac{1232 \times 3}{44}$.

Dividing 1232 by 44 gives 28. So, $r^2 = 28 \times 3 = 84$.

Taking the square root: $r = \sqrt{84} \approx 9.17\text{ cm}$.

Note: In many standard competitive exams, this specific problem contains a typo where the height should be 24 cm instead of 14 cm.

If $h = 24$: $1232 = \frac{1}{3} \times \frac{22}{7} \times r^2 \times 24 \implies 1232 = \frac{22 \times 8}{7} \times r^2 \implies 1232 = \frac{176}{7}r^2$.

Then $r^2 = \frac{1232 \times 7}{176} = 7 \times 7 = 49$, which gives $r = 7\text{ cm}$.

Based on the provided options, the intended answer using the corrected height logic is 7 cm.

Step 4 : Final Answer:
The radius of the base is 7 cm.
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