Question

What is the volume, in cubic inches, of a cone with a diameter of 6 inches and a height of 7 inches? Use 3.14 for pi. Round your answer to the nearest hundredth.

1 answer

To find the volume of a cone, we use the formula:

\[ V = \frac{1}{3} \pi r^2 h \]

where \(V\) is the volume, \(r\) is the radius, and \(h\) is the height.

First, we need to find the radius of the cone. The diameter is given as 6 inches, so the radius \(r\) is half of the diameter:

\[ r = \frac{6}{2} = 3 \text{ inches} \]

Next, we have the height \(h\) of the cone, which is given as 7 inches.

Now we can plug the values for \(r\), \(h\), and \(\pi\) (using \(3.14\)) into the volume formula:

\[ V = \frac{1}{3} \times 3.14 \times (3)^2 \times 7 \]

Calculating \( (3)^2 \):

\[ (3)^2 = 9 \]

Substituting this back into the volume formula:

\[ V = \frac{1}{3} \times 3.14 \times 9 \times 7 \]

Now calculate \(9 \times 7\):

\[ 9 \times 7 = 63 \]

Substituting this back gives:

\[ V = \frac{1}{3} \times 3.14 \times 63 \]

Calculating \(3.14 \times 63\):

\[ 3.14 \times 63 = 197.82 \]

Now calculate \(\frac{1}{3} \times 197.82\):

\[ V = \frac{197.82}{3} \approx 65.94 \]

Rounding to the nearest hundredth, we find:

\[ \boxed{65.94} \]

Thus, the volume of the cone is approximately \(65.94\) cubic inches.