Question

A roller is 4m long and has a diameter of 0.7m. It takes exactly 2000 rotations of the roller to level a road. If the cost of using the roller is Rs.4 per square metres, then the total cost of levelling the road is : Assume, $\pi = \frac{22}{7}$

A.
Rs.17600
B.
Rs.35200
C.
Rs.70400
D.
Rs.140800

Accepted Answer

C. Radius $r = 0.35$ m, height $h = 4$ m. Curved surface area = $2\pi rh = 2 	imes \frac{22}{7} 	imes 0.35 	imes 4 = 8.8$ sq m. Total area leveled in 2000 rotations = $8.8 	imes 2000 = 17600$ sq m. Total cost = $17600 	imes 4 = 	ext{Rs. } 70,400$.

Cost of Levelling Road

Explanation

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