ShmoopTube

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

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Peter Pan is offering a $500 reward for his, in case you see it.

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A person 5 ft. 10 in. tall casts a shadow 10 ft. 2 in. long.

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Approximately how tall is a tree that casts a 15 ft. 6 in. shadow?

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Here are the potential answers...

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Okay, we’ve got one fella whose shadow is nearly twice as long as he is tall.

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So, now in roughly the same spot…

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…is a tree whose shadow has got our hero’s shadow beat by over 5 feet.

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And we want to figure out… how tall is this tree?

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Well, what we have here is a simple ratio.

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The person’s five feet and 10 inches is to his 10 foot, 2 inch long shadow…

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…as “x” is to the tree’s 15 foot, 6 inch shadow.

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This problem is going to be a heck of a lot easier to deal with if we convert everything

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to inches, so…let’s do that.

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70 inches is to 122 inches…

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…as x is to 186 inches. We’ll set everything up as a fraction…

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70/122 = x/186…

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…and now we can just cross-multiply.

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122x = 13,020

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Divide both sides by 122 and x = 106.72.

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Now, remember…we converted everything to inches, so now we have to convert back to feet.

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106.72 divided by 12 is 8.89 feet…

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…which is option C.

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