ShmoopTube

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Here’s your shmoop du jour, brought to you by bicycles.

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We’re still holding onto the patent for handlebar moustaches…

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A bicycle that has tires with a diameter of 26 inches travels 2 miles.

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Approximately how many rotations did each tire make?

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And here are your potential answers…

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Oh, sure… the “bicycle” traveled 2 miles. No one at all was pedaling the dang thing.

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Sheesh…credit where credit is due, guys…

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All right, what have we got here?

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Each tire of our bike has a diameter of 26 inches… well, that should help us find the circumference.

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The formula we’re looking for is 2 pi r… or pi times d, because 2r is d.

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We already have our d… so...

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The perimeter of each tire is 26 pi inches… or 6.8 feet.

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If we weren’t already a metric conversion whiz, the problem tells us that one mile equals 5,280 feet…

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…so if our bike went TWO miles, then it went 10,560 feet. Which is…a lot of feet.

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All right, well… we’ve got our perimeter… now we want to know how many times each tire

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can turn that 6.8 feet over the course of its 2-mile run.

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We take 10,560 divided by 6.8…

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…and get roughly 1,550 rotations.

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Option E.

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Now I suppose you’re going to give the bike all the credit for solving this problem, too, aren’t you?

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