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You look like you could use a shmoopy question...

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On her first four tests, Jenny earned an 85,

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97, 79, and 84. Her uber-strict parents aren't letting her

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attend the State Math Finals unless she brings her overall mean up to at least 87.

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What must Jenny earn on her next test to be allowed to have... every young girl's dream come true?

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And here are the potential answers...

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OK so what is this question asking?

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Well it's really the advanced ninja version of taking averages.

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Poor Jenny took 4 tests and she's going to take another

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-- she will have taken 5 tests in total.

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And the TOTAL of these 5 tests must have an average of 87 -- or in other words, they

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must total to 5 times 87 or have a total of 435.

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So the answer comes from just adding up the previous 4 tests, subtracting that number

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from 435 and whatever is left is what she has to get to average an 87.

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So if we add the previous 4 tests we get a sub-total of 345.

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Subtract 345 from 435 and we get 90.

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So she has to get a 90 or better on the last test.

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Answer D.

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As in, "Deadly weapons."

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