Mei Li has a cube and a square-based pyramid. After measuring them, she discovers that they have the same height and base area. If the volume of the cube is 27 cubic inches, what is the volume of the pyramid?(1 point) Responses 3 cubic inches 3 cubic inches 13.5 cubic inches 13.5 cubic inches 9 cubic inches 9 cubic inches 27 cubic inches

1 answer

To find the volume of the pyramid, we can start by using the information given about the cube.

  1. Volume of the cube: The volume \(V\) of a cube with side length \(s\) is given by the formula: \[ V = s^3 \] According to the problem, the volume of the cube is 27 cubic inches: \[ s^3 = 27 \] Thus, we find the side length \(s\): \[ s = \sqrt[3]{27} = 3 \text{ inches} \]

  2. Height of the cube: Since the cube is also defined by its side length, the height of the cube is: \[ \text{Height of the cube} = s = 3 \text{ inches} \]

  3. Base area of the cube: The base area \(A\) of the cube, which is a square, is given by: \[ A = s^2 = 3^2 = 9 \text{ square inches} \]

Since Mei Li's square-based pyramid has the same height and base area as the cube, the pyramid also has a height of 3 inches and a base area of 9 square inches.

  1. Volume of the pyramid: The volume \(V\) of a square-based pyramid is given by the formula: \[ V = \frac{1}{3} \times \text{Base Area} \times \text{Height} \] Substituting the values for the base area and height: \[ V = \frac{1}{3} \times 9 \times 3 \] Simplifying it: \[ V = \frac{1}{3} \times 27 = 9 \text{ cubic inches} \]

So, the volume of the pyramid is 9 cubic inches.