Question

A solid cylinder has a total surface area of 231 cm². Its curved surface area is of the total surface area. Find the volume of the cylinder.

Answer 1

Given,

Total surface area of cylinder = 231 cm²

Curved surface area =\(\cfrac23\times\) 231 = 154 cm²

= 2πrh + 2πr² = 231

= 154 + 2πr² = 231

= height = h = 7 cm

So, volume of cylinder = πr²h = \(\cfrac{22}7\times\cfrac{7}2\times\cfrac{7}2\times\)7 = 269.5 cm³