Let as assume well is a solid right circular cylinder
Radius of cylinder (r)=3.5/2 = 1.75m
Height (or) depth of well = 16m.
Given that length of platform (l) = 27.5m
Breath of platform (b) = 7 cm
Let height of platform be x m
Since well is spread evenly to form platform
So equating (1) and (2)