Question

A well is dug 20 m deep and it has a diameter 7 m. The earth which is so dug out is spread on a rectangular plot 22 m long and 14 m broad. What is the height of platform formed?

Answer 1

Lets first find the volume of the mud dug out. Formula used will be r²h.

Hence we have volume = 22/7 × (7/2)² × 20

We also have the volume of the cuboid at L x B x H
Here L = 22 and B = 14, we need to find H

Since the two volumes are equal, we have
22 x 14 x H = 22/7 × (7/2)² × 20

Hence we get the Height of the platform as 2.5m.