Question:medium

A cylindrical water tank has radius $7\text{ m}$ and height $10\text{ m}$. What is its volume?}

Show Hint

Whenever a cylinder or circle problem gives a radius that is a multiple of 7 (7, 14, 21...) with $\pi=\frac{22}{7}$, work out the base area first -- it always comes out as a whole number -- then just multiply by the height. This avoids messy fraction cancellation in the full formula.
Updated On: Aug 17, 2026
  • $1540\text{ m}^3$
  • $490\text{ m}^3$
  • $980\text{ m}^3$
  • $3080\text{ m}^3$
Show Solution

The Correct Option is A

Solution and Explanation

Step 1: Understanding the Concept:
This question is based on the volume of a three-dimensional solid, specifically a cylinder.
The volume of a cylinder represents the total capacity of the tank and depends on the base area and the vertical height.
Step 2: Key Formula or Approach:
The volume \( V \) of a cylinder is given by the formula:
\[ V = \pi r^2 h \] Where:
\( r \) = radius of the cylinder.
\( h \) = height of the cylinder.
\( \pi \approx \frac{22}{7} \).
Step 3: Detailed Explanation:
We are given the following values in the problem:
Radius \( r = 7\text{ m} \)
Height \( h = 10\text{ m} \)
Now, substitute these values into the volume formula:
\[ V = \frac{22}{7} \times (7)^2 \times 10 \] Calculate the square of the radius first:
\[ 7^2 = 49 \] The expression becomes:
\[ V = \frac{22}{7} \times 49 \times 10 \] Cancel out the common factor of 7 from the denominator and 49:
\[ V = 22 \times 7 \times 10 \] First, multiply 22 by 7:
\[ 22 \times 7 = 154 \] Then, multiply by the height:
\[ 154 \times 10 = 1540 \] Since the dimensions are in meters, the volume will be in cubic meters.
Step 4: Final Answer:
The volume of the water tank is $1540\text{ m}^3$.
Was this answer helpful?
1


Questions Asked in CUET (UG) exam