ShmoopTube

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Here's your shmoop du jour, brought to you by Outward Bound. Don't worry—we won't

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throw you to the wolves.

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It is your first day of Outward Bound and you need to pitch a tent in the form of a

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triangular prism with the dimensions shown.

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How much material do you need to cover the entire tent?

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And here are your potential options...

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Since we're trying to find the amount of material needed to cover the tent, we need

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to find the surface area.

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First, we need to find the area of each individual shape

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in the triangular prism and then... add them all up.

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Let's start with the triangles that make up the front and back of the tent.

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They have a height of 5, and a base length of 24

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We can plug in these values to get the area of each triangle, which turns out to be 60

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square feet. There are two of these in the tent, so they

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have a total surface area of 120 square feet. As for the two remaining rectangles,

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we have a length of 40 feet, and a width of 13 feet; by calculating the area of each,

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we get 520 square feet. Again, we have two of these, so we have to

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multiply it by 2 to get 1040 square feet. We have to add the areas of the triangles

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and the rectangles to get our total surface area, and when we do that, we get 1,160 square

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feet of material needed. Option D is just right.

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