Question

The radius of the base of a solid cone is 21 cm and its height is 9 cm. What is the volume of the cone?

• A. 1980 Cm³
• B. 5940 Cm³
• C. 4158 Cm³
• D. 1386 Cm³

Answer 1

Answer:

C. 4158 Cm³

The volume of the cone is 4,158 cm³.

To find the volume of a cone, we use the formula:
$V = \frac{1}{3} \pi r^2 h$

Where:

• $r$ (Radius of the base) = 21 cm

• $h$ (Height of the cone) = 9 cm

• $\pi$ (Pi) = $\frac{22}{7}$

• $V$ (Volume) = ?

Substituting the Values

1. Write down the equation with the given numbers:
   $V = \frac{1}{3} \times \frac{22}{7} \times 21 \times 21 \times 9$

2. Simplify the terms (divide 21 by 7, and 9 by 3):
   $V = 1 \times 22 \times 3 \times 21 \times 3$

3. Multiply the remaining numbers:
   $V = 22 \times 189$

4. Final calculation:
   $V = 4,158$