Q28 of 47 Page 1

A 21 m deep well with diameter 6 m is dug and the earth from digging is evenly spread to form a platform 27 m × 11 m. Find the height of the platform.

Given, Diameter of well=6m


So, radius of well(r)=6/2=3m


Depth of well(h)= 21m



Let the height of the platform = h m


Volume of platform=Volume of the earth taken out


⇒ 27 × 11 × h=594


⇒


Therefore, Height of the platform=2m


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