Question

The circumference of circular faces of a frustum.

Answer 1

Given:

Circumference of the larger face (C₁) = 132 cm

Circumference of the smaller face (C₂) = 88 cm

π = `22/7`

Formula: Circumference (C) = 2πr

Finding the larger radius (r₁):

2πr₁ = 132

`2 xx 22/7 xx r_1 = 132`

`r_1 = (132 xx 7)/(2 xx 22)`

`r_1 = (132 xx 7)/44`

r₁ = 3 × 7

r₁ = 21 cm

Finding the smaller radius (r₂):

2πr₂ = 88

`2 xx 22/7 xx r_2 = 88`

`r_2 = (88 xx 7)/(2 xx 22)`

`r_2 = (88 xx 7)/44`

r₂ = 2 × 7

r₂ = 14 cm

The radii of the corresponding circular faces are 21 cm and 14 cm.