Multiply the edge lengths of a right rectangular prism with length 1/2

, width 1 1/2
, and height 3/4
to show that the product is the same as the volume you found by packing the prism with unit cubes with an edge length of 1/4
inch.

Cube method:
Number of cubes: 36
Volume of each cube: 1/4×1/4×1/4=1/64


Volume of the prism:

v=36×1/64


=36/64


=9/16 cubic units

(1 point)
Responses

1/2×3/2×3/2

1/2×11/2×3/4

1/2×1/2×3/4

1/2×3/2×3/4

1 answer

To find the volume of the right rectangular prism, we can multiply its edge lengths: length, width, and height.

Given edge lengths:

  • Length = \( \frac{1}{2} \)
  • Width = \( \frac{3}{2} \) (which is equivalent to \( 1 \frac{1}{2} \))
  • Height = \( \frac{3}{4} \)

We will multiply these values together:

\[ \text{Volume} = \text{Length} \times \text{Width} \times \text{Height} = \frac{1}{2} \times \frac{3}{2} \times \frac{3}{4} \]

Calculating this step-by-step:

  1. Multiply \( \frac{1}{2} \times \frac{3}{2} \):

\[ \frac{1 \times 3}{2 \times 2} = \frac{3}{4} \]

  1. Now multiply \( \frac{3}{4} \) by \( \frac{3}{4} \):

\[ \frac{3}{4} \times \frac{3}{4} = \frac{3 \times 3}{4 \times 4} = \frac{9}{16} \]

So, the volume of the prism is \( \frac{9}{16} \) cubic units.

Now we will check if this matches the volume calculated using the cube method.

From the cube method:

  • Number of cubes = 36
  • Volume of each cube = \( \frac{1}{4} \times \frac{1}{4} \times \frac{1}{4} = \frac{1}{64} \)

Volume of the prism calculated using the cube method:

\[ v = 36 \times \frac{1}{64} = \frac{36}{64} = \frac{9}{16} \text{ cubic units} \]

Both methods yield the same volume of \( \frac{9}{16} \) cubic units.

Now, regarding the responses, the correct multiplication of the dimensions that corresponds to our calculations is:

\( \frac{1}{2} \times \frac{3}{2} \times \frac{3}{4} \)

This matches the volume calculated through both methods.