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

Given,

Width of roller = 63 cm

Girth (perimeter) = 440 cm

= 2πR = 440

= 2 x \(\frac{22}{7}\) x R = 440

= R = \(\frac{440\times 7}{44}\) = 70 cm

thickness of roller = 4 cm

inner radius = R - thickness = 70 - 4 = 66 cm

Volume of cylindrical iron = π(R² - r²)l = \(\frac{22}{7}\) x (70² - 66²)63 = \(\frac{22}{7}\)x 594 x 63 = 107712 cm³