A radius of the base of a right circular cone is 6 cm and its slant height is 28 cm. The curved surface area of the cone is----

Options

A. 268 sq. cm
B. 528 sq. cm
C. 462 sq. cm
D. 658 sq. cm

Answer

To find the curved surface area of a right circular cone, we can use the formula:

\[ \text{Curved Surface Area (CSA)} = \pi r l \]

where:
- \( r \) is the radius of the base of the cone,
- \( l \) is the slant height of the cone,
- \( \pi \) is a constant approximately equal to \( 3.14 \) or \( \frac{22}{7} \).

### Step-by-Step Solution:

1. **Identify the given values:**
- Radius of the base \( r = 6 \) cm
- Slant height \( l = 28 \) cm

2. **Substitute the values into the formula:**
\[ \text{CSA} = \pi r l = \frac{22}{7} \times 6 \times 28 \]

3. **Calculate \( r \times l \):**
\[ r \times l = 6 \times 28 = 168 \]

4. **Now substitute this value back into the equation:**
\[ \text{CSA} = \frac{22}{7} \times 168 \]

5. **Multiply \( 22 \) by \( 168 \):**
\[ 22 \times 168 = 3696 \]

6. **Now divide by \( 7 \):**
\[ \text{CSA} = \frac{3696}{7} = 528 \text{ cm}^2 \]

### Final Answer:
The curved surface area of the cone is \( 528 \text{ cm}^2 \).