Question

A drinking glass is in the shape of a frustum of a cone of height 14 cm. The diameters of its two circular ends are 4 cm and 2 cm. The capacity of the glass is $102\frac{2}{3}c{m}^3$.

• A. True
• B. False

Answer 1

The correct option is A

True

Height of frustum of cone = h = 14 cm

Radius of first end = $r_1$ = 1 cm

Radius of second end = $r_2$ = 2 cm

Volume of frustum of cone = $\frac{1}{3}$ $\pi .h\left(\right(r_1{)}^2+(r_2{)}^2+(r_1).(r_2\left)\right)$

=$\frac{1}{3}$ × $\frac{22}{7}$ × 14$(1^2+2^2+(1\left)\right(2\left)\right)$

= $\frac{1}{3}$ × $\frac{22}{7}$ × 14 × 7= $\frac{308}{3}$ = 102$\frac{2}{3}$ $c{m}^3$