A sphere, a cylinder and a cone are of the same radius and same height. Find the ratio of their curved surface.

Explanation

Let radius be `r` and height be `h`

So, Height of the cone = Height of the cylinder = Height of the sphere = `2r`

Now, C.S.A of sphere = `4pir^2`

C.S.A of cone = `pirl` = `sqrt(5)(pir)^2`

C.S.A of cylinder = `2pirh` = `4pir^2`

Here, l is slant height.

`l=sqrt(r^2+h^2)`=`sqrt(4r^2+r^2)`

`l=rsqrt5`

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