Question

From a rectangular field 80m long and 20m wide, a cuboidal pit of dimensions 20m *10m is dug. the Earth obtained from the pit is evenly spread over the remaining portion of the field. as a result the level of the field of raised by 1.5m.find the depth of the pit

Answer 1

 3: A 20 m deep well with diameter 7 m is dug and the earth from digging is evenly spread out to form a platform 22 m by 14 m. Find the height of the platform.

Solution: Radius of well = 3.5 m, depth of well = 20 m

Dimensions of rectangular platform = 22 m x 14 m

Volume of earth dug out

Area of top of platform = Area of Rectangle – Area of Circle

(because circular portion of mouth of well is open)

Height = Volume/Area

Know that this won't help you much but still you can refer your answer