Question

A hollow garden roller, 63 cm wide with a girth of 440 cm, is made of 4 cm thick iron. Find the volume of the iron.

Answer 1

We have,

Width of roller = 63 cm

Thickness of roller = 4 cm

Girth (perimeter) = 440 cm

2πR = 440

2 × 22/7 × R = 440

R = 440×7 / 2×22

= 70cm

Inner radius = R – thickness = 70 – 4 = 66 cm

Volume of cylindrical iron = π(R² – r²) l

= 22/7 × (70² – 66²) × 63

= 22/7 × 594 × 63

= 107712 cm³

∴ The volume of iron is 107712 cm³