Question 6 (Multiple Choice, Worth 1 point)

The radius of the cone is 7 in and [tex]\( y = 25 \)[/tex] in. What is the volume of the cone in terms of [tex]\(\pi\)[/tex]?

[tex]\( y \)[/tex]
[tex]\( x \)[/tex]



Answer :

To find the volume of the cone given the radius and the slant height, let's go through the steps methodically:

1. Identify the given values:
- Radius (r) = 7 inches
- Slant height (y) = 25 inches

2. Determine the height (h) of the cone:
The height of the cone can be found using the Pythagorean theorem in the right triangle formed by the radius, the height, and the slant height. We know:
[tex]\[ y^2 = r^2 + h^2 \][/tex]
Substituting the given values:
[tex]\[ 25^2 = 7^2 + h^2 \][/tex]
[tex]\[ 625 = 49 + h^2 \][/tex]
Solving for [tex]\( h \)[/tex]:
[tex]\[ h^2 = 625 - 49 \][/tex]
[tex]\[ h^2 = 576 \][/tex]
[tex]\[ h = \sqrt{576} \][/tex]
[tex]\[ h = 24 \][/tex]

3. Calculate the volume (V) of the cone:
The formula for the volume of a cone is given by:
[tex]\[ V = \frac{1}{3} \pi r^2 h \][/tex]
Substituting the values for the radius and height:
[tex]\[ V = \frac{1}{3} \pi (7^2) (24) \][/tex]
[tex]\[ V = \frac{1}{3} \pi (49) (24) \][/tex]
[tex]\[ V = \frac{1}{3} \pi (1176) \][/tex]
[tex]\[ V = 392 \pi \][/tex]

Therefore, the volume of the cone in terms of π is [tex]\( 392 \pi \)[/tex] cubic inches.