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Question
If the lateral surface of a cylinder is 94.2 cm2 and its height is 5 cm, then find (i) radius of its base (ii) its volume. [Use π = 3.14]
Solution
(i) Height (h) of cylinder = 5 cm
Let radius of cylinder be r.
CSA of cylinder = 94.2 cm2
2πrh = 94.2 cm2
(2 × 3.14 × r × 5) cm = 94.2 cm2
r = 3 cm
(ii) Volume of cylinder = πr2h
= (3.14 × (3)2 × 5) cm3
= 141.3 cm3
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