Question

Find the diameter of a cone that has a volume of 29.31 cubic inches and a height of 7 inches. Use 3.14 for pi.

4 inches

2 inches

8 inches

6 inches

Answer 1

@luka1998

What is the formula for the volume of a right circular cone?

Answer 2

The volume of a cone can be found by multiplying 1/3 the area of its circular base times the height of the cone.

Answer 3

V =1/3* pi * r^2 * h where pi*r^2 is the area of the base and h is the height

29.31 = 1/3 * 3.14 * r^2 * 7 @luka1998 Solve the equation for r.

Answer 4

@luka1998

What is (1/3) * 3.14 * 7 -- > Just multiply those three numbers and post what you get.

Answer 5

@luka1998

Answer 6

7.326

Answer 7

Okay, so

29.31 = 1/3 * 3.14 * r^2 * 7

29.31 = 7.326 * r^2

29.31/7.326 = r^2

So, divide 29.31 by 7.327 and take the square root to get r.

Don't forget to double r at the end because the problem asks for diameter.

Answer 8

4

Answer 9

The diameter is 4; yes, that is what I got.

Answer 10

@Directrix THX

Answer 11

You are welcome.

Answer 12

\[V = \frac{ 1 }{ 3 }\pi \times r^2h \rightarrow \sqrt{\frac{ 29.31 - 1.05 }{ 7 }} \times 2 = r \rightarrow r = 2, d = r \times 2, d = 4\]