What is the volume of this prism?

Start by finding the area of the base of the prism. Solve on paper, and then enter your answer on Zearn. You can use the Zearn calculator to help with your calculations.
3D shape with L-shaped base labeled with side lengths in cm: 12, 8, 6, 10. A side length of 3 cm connects the two bases.
Area of the base, B Height of the prism, h Volume, V = B · h
cm
2
? cm ? cm
3

1 answer

To find the volume of the prism, we first need to determine the area of the L-shaped base and then multiply it by the height of the prism.

  1. Find the Area of the Base (B):

The base is L-shaped, so we can divide it into two rectangles. The measurements of the sides given are:

  • Rectangle 1 has dimensions: 12 cm (length) and 8 cm (height).
  • Rectangle 2 has dimensions: 10 cm (length) and 6 cm (height).

To find the area of the L-shaped base, we do the following:

Area of Rectangle 1: \[ A_1 = \text{length} \times \text{height} = 12 , \text{cm} \times 8 , \text{cm} = 96 , \text{cm}^2 \]

Area of Rectangle 2: \[ A_2 = \text{length} \times \text{height} = 10 , \text{cm} \times 6 , \text{cm} = 60 , \text{cm}^2 \]

  1. Combine the areas: Since the rectangles overlap along one edge, subtract the area of the overlap. The overlap dimensions are 6 cm by 6 cm (the shorter height of Rectangle 2 does not exceed Rectangle 1):

Area of the Overlapping Section: \[ A_{\text{overlap}} = 6 , \text{cm} \times 6 , \text{cm} = 36 , \text{cm}^2 \]

Now, the total area of the L-shaped base would be:

\[ B = A_1 + A_2 - A_{\text{overlap}} = 96 , \text{cm}^2 + 60 , \text{cm}^2 - 36 , \text{cm}^2 = 120 , \text{cm}^2 \]

  1. Find the Height of the Prism (h): The height of the prism is given as 3 cm.

  2. Calculate the Volume (V): Using the formula for the volume of a prism, \( V = B \cdot h \): \[ V = 120 , \text{cm}^2 \times 3 , \text{cm} = 360 , \text{cm}^3 \]

Final Answers:

  • Area of the base, \( B = 120 , \text{cm}^2 \)
  • Height of the prism, \( h = 3 , \text{cm} \)
  • Volume of the prism, \( V = 360 , \text{cm}^3 \)

You can use this information to enter your answers in Zearn.