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Time for your daily dose of Shmoop. So open wide.

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According to the information given below, how many times faster is Car A than Car D?

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Car A is twice as fast as B.

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Car B is three times as fast as C.

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Car C is twice as fast as D.

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And Car D is half as fast as C.

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And here are the potential answers:

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So this is a bake-your-own-algebraic-equation kind of problem.

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It says that car A is twice as fast as car B… so we can write A equals 2B…

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Car B is three times as fast as Car C so B = 3C…

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Car C is twice as fast as Car D so C = 2D…

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Car D is half as fast as Car C so D = 1/2C…

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…and Cars 2 is half as good as The Incredibles.

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Okay, now we just have to simplify.

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Let's just connect everything that we know B equals…

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B = 3C = 3(2D) = 6D.

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It takes 6 D’s to make one B. 

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But the question is asking us to compare A with D…

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so we somehow need to map B onto A.

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We know that it takes 2 B’s to make an A. So if it takes 6 D's to make one B, then it

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should take 2 times 6 D's to make an A… or 12 D's.

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Answer E.

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So car A is like a Ferrari and car D is like your portly grandpa’s lawnmower.

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