Question

The volume of a frustum cone is 560 $m^3$, whose base and upper area of a circle is 90 and 10 $m^2$. Find the height of the cone.

• A. 40 cm
• B. 34 cm
• C. 24 cm
• D. 54 cm

Answer 1

The correct option is C 24 cm

Volume of a frustum cone = $\frac{1}{3}(A_1+A_2+\sqrt{A_1{A}_2})h$

560 = $\frac{1}{3}(90+10+\sqrt{40\times 10})\times h$

560 = $\frac{1}{3}(50+\sqrt{400})\times h$

560 = $\frac{1}{3}(50+20)\times h$

$560\times 3$ = $70\times h$

h = 1,680/70 = 24$cm$