Question

A 80 m by 64 m rectangular lawn has two roads, each 5 m wide, running through its middle, one parallel to its length and the other parallel to its breadth. Find the cost of gravelling the reads at ₹ 40 per m².

Answer 1

The length and breadth of the lawn are 80 m and 64 m, respectively.

The layout of the roads is shown in the figure below:

Area of the road ABCD = 80 x 5 = 400m²

Area of the road PQRS = 64 x 5 = 320m²

Clearly, the area EFGH is common in both the roads

Area EFGH = 5 x 5 = 25m²

Area of the roads = 400 + 320 - 25

= 695m²

Given:

Cost of gravelling 1 m² area = Rs 40

Cost of gravelling 695 m² area = 695 x 40

= Rs 27,800