Question

A well diameter3m is dug 14m deep. The soil taken out if it is spread evenly all around it to a width of 5m to from an embankment. Find the height of the embankement.

Answer 1

volume of well = π × 3/2 × 3/2 × 14
= 63/2π m3
radius of embankment = 3/2+ 5 = 13/2m .
volume of embankment = π(13/2)^2×H - π63/ ( 3/2)^2×H. = 40π H
according to question,
40π H = 63/2π
H = 63 / 2 × 40
H=0.7875m
I hope it help you