Question

The radii of the circular ends of a frustum of height 6 cm are 14 cm and 6 respectively. Find the slant height of the frustum.

Answer 1

Radius of the bigger circle = R = 14 cm

Radius of the smaller circle = r = 6 cm

Height of the frustum = h = 6 cm

Slant height of frustum = ​l = $\sqrt{h^2+(R-r{)}^2}$

$\Rightarrow$ l = $\sqrt{6^2+(14-6{)}^2}$

$\Rightarrow$ l = $\sqrt{100}$

$\Rightarrow$ l = 10 cm