Use the image to answer the question.

An illustration shows a triangular pyramid and a triangular prism. The edges that are not visible are marked as dashed lines. The triangular pyramid has the triangular face as its base. The sides of of the triangular base measure 3 inches and 5 inches. The perpendicular height of the pyramid is 8.41 inches. The triangular prism has its triangular face as the base. The sides of the triangular base measure 3 inches and 5 inches. The length of the side is 8.41 inches.

Which shape has the larger volume? How much larger is it?

(1 point)
Responses

The pyramid has a larger volume by three times.
The pyramid has a larger volume by three times.

The volumes are the same.
The volumes are the same.

The prism has a larger volume by three times.
The prism has a larger volume by three times.

The prism has a larger volume by 1/3 times.
The prism has a larger volume by Start Fraction 1 over 3 End Fraction times.
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1 answer

To determine which shape has the larger volume, we can calculate the volumes of both the triangular pyramid and the triangular prism.

Volume of the Triangular Pyramid (V_pyramid):
The formula for the volume of a triangular pyramid is:
\[ V = \frac{1}{3} \times \text{Base Area} \times \text{Height} \]

  1. Calculate the base area of the triangular base:
    For a triangle, the area can be calculated using Heron's formula, which requires the lengths of all three sides. However, we will use the simpler formula for the area of a triangle with base and height.

    We can find the height of the triangle with sides of lengths 3 inches and 5 inches by using the fact that the third side (the side opposite to the height) can be calculated using the Pythagorean theorem, or we can assume this triangle is a right triangle for the sake of volume. But since we don't have the third side, we will proceed to calculate the area assuming we calculate the height from the 3-inch side as the base:

    However, without loss of generality we can find an approximate area using a general triangle area formula (as an assumption of a right triangle can mislead): Let's say we assume a height proportion effectively gives: The height corresponding to base 3 can be estimated using proportional segments but we will revert to: Direct area approximation:

    Using \( A = \frac{base \times height}{2} \) where the height derived via \( \sqrt{\text{(max)\text{/2 height triangle)}} \) could set: \[ \text{Base Area} \approx \frac{3 \times 5}{2} = 7.5 \text{ sq inches (assumed)} \]

  2. Volume of the pyramid using height of 8.41 inches: \[ V_{pyramid} = \frac{1}{3} \times 7.5 \times 8.41 \approx 19.83 \text{ cubic inches} \]

Volume of the Triangular Prism (V_prism):
The formula for the volume of a triangular prism is:
\[ V = \text{Base Area} \times \text{Length} \]

Using the same triangle base area of 7.5 sq inches from above, and the length being 8.41 inches: \[ V_{prism} = 7.5 \times 8.41 \approx 63.07 \text{ cubic inches} \]

Comparison:
Now we compare the two volumes: \[ V_{prism} \approx 63.07 \text{ cubic inches}, \quad V_{pyramid} \approx 19.83 \text{ cubic inches} \]

Thus, the prism has a larger volume. To find out how much larger it is: \[ 63.07 - 19.83 = 43.24 \]

In terms of ratios: \[ \frac{ \text{V}{prism}}{ \text{V}{pyramid}} = \frac{63.07}{19.83} \approx 3.17 \text{ times larger} \]

Conclusion: The prism has a larger volume by more than three times, specifically in cubic inch approximation of differences given large scales.

Therefore, the correct response is: The prism has a larger volume by approximately three times.