Question

The curved surface area of a cylinder is 1320 cm² and its base has diameter 21 cm. Find the height of the cylinder.

 

Answer 1

\[\text{ Let h be the height of the cylinder .}  \]
\[\text{ Given: }  \]
\[\text{ Curved surface area, S = 1320 {cm}} ^2 \]
\[\text{ Diameter, d = 21 cm } \]
\[\text{ Radius, } r = 10 . 5\]
\[ S = 2\pi rh\]
\[1320 = 2\pi \times 10 . 5 \times h\]
\[ h = \frac{1320}{2\pi \times 10 . 5}\]
\[ h = 20 \text{ cm } \]