Question

Molly is painting a model house and needs to know how much paint she will need. She knows the surface area of the prism is 216 square inches and the surface area of the pyramid is 84 square inches.
What is the area Molly needs to paint? Follow the steps to solve this problem.
1. Which surface is shared by the two solids? What are the dimensions of this surface?
The surface that is shared by the two solids is the top of the cube that is the same as the square base of the pyramid.
2. There is another surface that Molly does not need to paint, because it won’t show when she displays the model house. Describe that surface, and explain why it doesn't need to be painted.
She doesn't need to paint the bottom because you cant see the bottom.
3. To find the area Molly needs to paint, she should add the surface areas of both solids and subtract:
Circle the correct answer.
twice the area of the triangle
twice the area of the square
three times the area of the square
the area of the square
4. Find the area Molly needs to paint. Show your work, and be sure to include units with your answer.

Answer 1

Answer:

Step-by-step explanation:

Part 1) The surface that is shared by the two solids is the top of the cube that is the same that the square base of the pyramid

Part 2) The dimensions of this surface are 6 in x 6 in

Part 3) Molly needs to paint 228 square inches

The picture of the question in the attached figure

Part 1) Which surface is shared by the two solids?

we know that

The surface that is shared by the two solids is the top of the cube that is the same that the square base of the pyramid

Part 2)  What are the dimensions of this surface?

The surface is a square with side length 6 inches

so

The dimensions of this surface are 6 in x 6 in

Part 3) what is the area molly needs to paint?

we know that

The area that Molly needs to paint is equal to the surface area of the cube plus the surface area of the pyramid minus two times the area of the surface that is shared by the two solids

so

therefore

Molly needs to paint 228 square inches