Susie runs an ice cream stand that also sells snow cones served in paper cones. The paper cones she usually uses have a diameter of 6in and a height of 2in, but her supplier is out of them. As a replacement, she purchases paper cones with a diameter of 2in and a height of 6in. How do the volumes of the original and replacement cones compare?

the original and replacement cones have the same volume
the original cone has a greater volume than the replacement
the replacement cone has a greater volume than the original
the original cone holds 2 times the amount as the replacement

1 answer

To compare the volumes of the original and replacement cones, we can use the formula for the volume of a cone:

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

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

  1. Volume of the original cone:

    • Diameter = 6 inches, so radius \( r = \frac{6}{2} = 3 \) inches
    • Height \( h = 2 \) inches \[ V_{\text{original}} = \frac{1}{3} \pi (3^2)(2) = \frac{1}{3} \pi (9)(2) = \frac{18}{3} \pi = 6 \pi \text{ cubic inches} \]
  2. Volume of the replacement cone:

    • Diameter = 2 inches, so radius \( r = \frac{2}{2} = 1 \) inch
    • Height \( h = 6 \) inches \[ V_{\text{replacement}} = \frac{1}{3} \pi (1^2)(6) = \frac{1}{3} \pi (1)(6) = \frac{6}{3} \pi = 2 \pi \text{ cubic inches} \]
  3. Comparison of the volumes:

    • Original cone volume: \( 6 \pi \)
    • Replacement cone volume: \( 2 \pi \)

From this, we see that:

\[ V_{\text{original}} = 6 \pi, \quad V_{\text{replacement}} = 2 \pi \]

To compare:

\[ 6 \pi > 2 \pi \]

This means the original cone has a greater volume than the replacement cone.

Conclusion:

The original cone has a greater volume than the replacement.