The radii of the circular ends of a frustum of height 6cm are 14cm and 6cm respectively. Find the lateral surface area and total surface are of the frustum.

Explanation

Let height of frustum` h=6` and

Radius of the circular ends of the frustum are

`r1=14 , r2=6`

let l be the slant height

`:. l^2 = h^2 + (r1 – r2)^2`

`:. l^2 = 6^2 + (14-6)^2`

`:. l^2 = 36+64`

`:. l^2 =100`

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