Q5 of 52 Page 160

The diameter and length of a roller is 120 cm and 84 cm respectively. To level the ground, 200 rotations of the roller are required. Find the expenditure to level the ground at the rate of Rs. 10 per sq. m

Diameter of roller = 120 cm


⇒ Radius, r = 60 cm


Length Of Roller, h = 84 cm




⇒ AR = 31680 sq. cm


Total area of ground, AG = 200 × AR


⇒ AG = 6336000 cm2


As 1 m2 = 104 cm2


⇒ AG = 633.6 sq.m


Rate to level the ground = Rs. 10 per sq.m



⇒ Total Expenditure = 633.6 × 10


⇒ Total expenditure = Rs. 6336


∴ Total expenditure to level the road will be Rs. 6336


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