Question

The volume of a frustum cone is 2,700 $i{n}^3$, whose base and upper area of a circle is 20 and 5 $i{n}^2$. Find the height of the cone.

• A. 221.42 in
• B. 231.42 in
• C. 211.42 in
• D. 201.42 in

Answer 1

Answer: (B)

231.42 in

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

2,700 = $\frac{1}{3}(20+5+\sqrt{20\times 5})\times h$

2,700 = $\frac{1}{3}(25+\sqrt{100})\times h$

2,700 = $\frac{1}{3}(25+10)\times h$

$2,700\times 3=35\times h$

$h=\frac{8,100}{35}$

$h=231.42in$