If the lateral surface of a cylinder is 94.2 cm2 and its height is 5 c

1.	If the lateral surface of a cylinder is 94.2 cm2 and its height is 5 cm, find: i) radius of its base (ii) volume of the cylinder
Answer» Lateral surface of the cylinder = 94.2 cm² Height of the cylinder = 5 cm Let ‘r’ be the radius. (i) Lateral surface of the cylinder = 94.2 cm² 2πrh = 94.2 or 2 x 3.14 x r x 5 = 94.2 or 31.4 x r = 94.2 or r = 3 cm (ii) Volume of the cylinder = πr²h = (3.14 x 3² x 5) cm³ = 141.3 cm³

If the lateral surface of a cylinder is 94.2 cm2 and its height is 5 cm, find: i) radius of its base (ii) volume of the cylinder

Answer»

Lateral surface of the cylinder = 94.2 cm²

Height of the cylinder = 5 cm

Let ‘r’ be the radius.

(i) Lateral surface of the cylinder = 94.2 cm²

2πrh = 94.2

or 2 x 3.14 x r x 5 = 94.2

or 31.4 x r = 94.2

or r = 3 cm

(ii) Volume of the cylinder = πr²h

= (3.14 x 3² x 5) cm³

= 141.3 cm³