Question

The slant height of a frustum of a cone is 10cm. If the height of the frustum is 8cm then find the difference of the radii of its two circular ends.

Answer 1

l= root(R1-R2)^2+H^2
10=root(R1-R2)^2+64
100=(R1-R2)^2
100-64=(R1-R2)^2
R1-R2= 6 cm

Answer 2

Slant height = 10 cm
Height of frustum = 8 cm


l = ✓h² + ( R - r)²

l² = h² + ( R - r )²

100 = 64 + ( R - r)²

36 = ( R - r)²

6 = R - r

Therefore the difference between the radii of its two circular ends is 6 cm

Hope this helps you....:)