Question

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

• A. $1540\text{ m}^3$
• B. $490\text{ m}^3$
• C. $980\text{ m}^3$
• D. $3080\text{ m}^3$

Hint:

Always check the units! Since both radius and height are in meters ($m$), the volume will be in cubic meters ($m^3$). If they were different, you would need to convert them first.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
The volume of a cylinder represents the total space occupied by the object. Since the base of a cylinder is a circle, the volume is calculated by multiplying the area of the circular base by the height of the cylinder.

Step 2: Identifying the Formula and Values:
The formula for the volume ($V$) of a cylinder is: \[ V = \pi r^2 h \] Given values:
• Radius ($r$) = $7\text{ m}$
• Height ($h$) = $10\text{ m}$
• $\pi \approx \frac{22}{7}$

Step 3: Calculation:
Substitute the values into the formula: \[ V = \frac{22}{7} \times (7)^2 \times 10 \] \[ V = \frac{22}{7} \times 49 \times 10 \] Cancel the common factor of $7$: \[ V = 22 \times 7 \times 10 \] \[ V = 154 \times 10 = 1540\text{ m}^3 \]

Step 4: Final Answer:
The volume of the water tank is $1540\text{ m}^3$.