Question

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 a platform?

Answer 1

Given, height of the well=20m
Diameter =7m=7/2m
Volume of the well= pir2h
=22/7×7/2×7/2×20
=22×7×5m
=770m3
Now, Lenght of the plot =22m
Breadth of the plot =14 m
Area =l×b
=14×22
=308m2
Therefore, Height of the platform formed =Volume of well/area of plot
=770/308=2.5m
Hope it helps u.
Pls mark my answer as brainliest.
In case of any doubt pls comment below

Answer 2

⇒ Given:- Height (h) of well :- 20m

Diameter (d) :- 7 m

Radius (r) :- 7/2 m

Volume of earth platform :- 22 m by 14m

⇒ To find :- Height of the platform:- ?

⇒ Solution:-

Volume of cylinder of radius 7/2 m and height 20 m

Volume of cylinder :- π(r^2)(h)

= 22/7×(7/2^2)×20 m^3

= 770 m^3

Let the height raised by 22 m × 14 m platform be equal to h metres

Therefore,

Volume of the earth in platform = Volume of the earth taken out of the well

22 × 14 × h = 770

h = 770/22 × 14 m

h = 5/2 m

h = 2.5 m

Hence , the height of the platform is 2.5 m.