Question

Justin built a display stand out of two rectangular prisms. The smaller rectangular prism is 2 inches tall, 4 inches wide, and 6 inches long. The larger rectangular prism is 5 inches tall, 8 inches wide, and 10 inches long. He painted the entire outside of each prism before he put the prisms together. What was the total surface area, in square inches, that Justin painted on both rectangular prisms? (DO NOT include the unit in your answer!)

Answer 1

416

Explanation:

We simply must find the surface area of each prism and then add them together. To the find the surface area of a rectangular prism, we must find the area of each of the sides and then add them all together.

So for the first prism, the area of each of the sides are:

2*(2*4)=16 (this is because are two sides with the measurements 2*4)

2*(2*6)=12

2*(4*6)=48

total: 76

For the second prism:

2*(5*8)=80

2*(5*10)=100

2*(8*10)=160

total: 340

Now that we have the surface area of each of the prisms, we must add them together. Therefore, 340+76=416. The answer is 416.