ShmoopTube

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Perimeter of a Rectangle, a la Shmoop. Lance Armstrong has had a media storm of evil-wishers

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show up at his doorstep recently.

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He needs to install a state-of-the art video-surveillance Wi-Fi-controlled weapon-of-mass-destruction-armed

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electric fence.

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But he donated nearly all his money to cancer research.

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So he’s going to have to buy a fence on the cheap…

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… which means he needs to know how to build a rectangular fence around his compound with

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the smallest perimeter. Lance knows that he needs at least 36 square

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miles of land for his palatial mansion, biking trails, and factory of lies.

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What is the smallest possible perimeter for his rectangle?

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The formula for the area of a rectangle is length times width…

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…while the formula for the perimeter is the sum of 2 times the length and 2 times

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the width. Or the sum of all four sides.

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To get an area of 36, here our options for the rectangle’s dimensions:

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36 by 1 18 by 2

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12 by 3 9 by 4

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and 6 by 6.

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And here are their corresponding perimeters: 70, 40, 30, 26, and 24.

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Of these choices, 24 is the smallest perimeter possible.

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And good thing it’s one of our answer choices!

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Hello, answer (B).

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Lies, Lance, lies.

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