MENU
Question -

A 16 m deep well with diameter 3.5 m is dug up and the earth from it is spread evenly to form a platform 27.5 m by 7m. Find the height of the platform?



Answer -

Let us assume the wellto be a solid right circular cylinder

Radius(r) of thecylinder = 3.5/2 m = 1.75 m

Depth of the well orheight of the cylinder (h) = 16 m

We know that,

Volume of the cylinder(V1) = πr2h

= π × 1.752 ×16

Given,

The length of theplatform (l) = 27.5 m

Breadth of theplatform (b) =7 m

Now, let the height ofthe platform be x m

We know that,

Volume of therectangle = l*b*h

V2 =27.5*7*x

As the earth dug up isspread evenly to form the platform

Volumes of both, thewell and the platform should be the same.

V1 = V2

π × 1.75 × 1.75 × 16 =27.5 × 7 × x

x = 0.8 m = 80 cm

Therefore, the heightof the platform is 80 cm.

Comment(S)

Show all Coment

Leave a Comment

Free - Previous Years Question Papers
Any questions? Ask us!
×