Question

The radius and height of a cylinder are in the ratio 5:7 and its curved surface area is 5500 sq.cm. Find its radius and height.

Answer 1

Let the radius be 5x and the height be 7x

C.S.A of a cylinder = 5500 sq.cm.

2πrh = 5500

`2 xx 22/7 xx 5x xx 7x` = 5500

2 × 22 × 5 × x² = 5500

x² = `5500/(2 xx 22 xx 5)`

x² = 25 cm

x = 5 cm

Radius of the cylinder = 5 × 5 = 25 cm

Height of the cylinder = 7 × 5 = 35 cm