Use the image to answer the question.

An illustration shows a triangle with its base as 20 feet and its perpendicular height as 6 feet.

A prism and a pyramid both have this triangular base. If both shapes have the same height and the volume of the prism is 600 ft.3 , what is the volume of the pyramid?

(1 point)
Responses

400 ft.3
400 ft. cubed

200 ft.3
200 ft. cubed

600 ft.3
600 ft. cubed

1,800 ft.3
1,800 ft. cubed
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1 answer

To find the volume of the pyramid, we need to know the formula for the volume of a pyramid and compare it with that of a prism.

  1. Volume of a Prism: The formula for the volume of a prism is: \[ V = B \cdot h \] where \( B \) is the area of the base and \( h \) is the height.

  2. Volume of a Pyramid: The formula for the volume of a pyramid is: \[ V = \frac{1}{3}B \cdot h \] where \( B \) is the area of the base and \( h \) is the height.

We know:

  • The volume of the prism is \( 600 , \text{ft}^3 \).
  • The height \( h \) of both the prism and pyramid is the same.

Given that both the prism and pyramid have the same base area, we can calculate the base area \( B \) of the triangle:

\[ B = \frac{1}{2} \times \text{base} \times \text{height} = \frac{1}{2} \times 20 , \text{ft} \times 6 , \text{ft} = 60 , \text{ft}^2 \]

Since the volume of the prism is given: \[ 600 = B \cdot h \] Substituting the base area \( B = 60 \): \[ 600 = 60 \cdot h \] Solving for \( h \): \[ h = \frac{600}{60} = 10 , \text{ft} \]

Now we can calculate the volume of the pyramid using the same base area and height:

\[ V_{\text{pyramid}} = \frac{1}{3}B \cdot h = \frac{1}{3} \times 60 , \text{ft}^2 \times 10 , \text{ft} = \frac{600}{3} = 200 , \text{ft}^3 \]

Thus, the volume of the pyramid is 200 ft.³.

So the correct response is: 200 ft.3 or 200 ft. cubed.