Question

An ice cream shop currently sells soft-serve ice cream in cones that have a radius of 3 inches and a height of 6 inches. The shop wants to offer a wider cone for their hard-serve ice cream that has the same volume as their existing cone but a wider radius of 4 inches. What will be the height, to the nearest inches, of the new cone

Answers

GPT-4o mini
To find the height of the new cone, we first need to calculate the volume of the existing soft-serve ice cream cone.

The volume \( V \) of a cone is given by the formula:

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

where \( r \) is the radius and \( h \) is the height of the cone.

For the existing cone, the radius \( r \) is 3 inches and the height \( h \) is 6 inches.

Substituting these values into the volume formula:

\[
V = \frac{1}{3} \pi (3^2)(6)
\]
\[
V = \frac{1}{3} \pi (9)(6)
\]
\[
V = \frac{1}{3} \pi (54)
\]
\[
V = 18\pi \text{ cubic inches}
\]

Now, we want to find the height of the new cone with a radius of 4 inches that has the same volume of \( 18\pi \) cubic inches.

Let the height of the new cone be \( h \). We will use the same volume formula:

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

Substituting the radius of the new cone \( r = 4 \) inches and setting the volume equal to \( 18\pi \):

\[
18\pi = \frac{1}{3} \pi (4^2) h
\]

Now calculate \( (4^2) \):

\[
(4^2) = 16
\]

Substituting this back into the equation:

\[
18\pi = \frac{1}{3} \pi (16) h
\]

We can cancel \( \pi \) from both sides:

\[
18 = \frac{1}{3} (16) h
\]

To eliminate the fraction, multiply both sides by 3:

\[
54 = 16h
\]

Now, solve for \( h \):

\[
h = \frac{54}{16} = 3.375
\]

Rounding to the nearest inch gives:

\[
h \approx 3 \text{ inches}
\]

Thus, the height of the new cone is \( \boxed{3} \) inches.