ShmoopTube

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Here’s an unshmoopy question you’ll find on an exam somewhere in life.

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Which of the following is the same as x plus 1 over 2… plus 3x over 5… equals 7/10?

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And here are the potential answers…

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So… what is this question asking?

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Can we simplify? Ask Henry David Thoreau.

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The fact that the 2 and the 5 in the first two denominators can be multiplied

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to get 10 should jump right out at us…

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Ok, so let’s start multiplying the top and bottom of the first term by 5…

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and we get 5x+5 over 10.

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Then the next term top and bottom get multiplied by 2… and we get 6x over 10.

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And finally… leave 7 over 10 as is. We’ve already got what we want on the bottom.

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Now multiply both sides by 10 to eliminate the denominators altogether…

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and we get 11x + 5 is 7.

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Answer B.

01:05

As in, “Boxer shorts.”

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