ShmoopTube

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You have the right to remain shmoopy.

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If your history test scores are 65, 71, 76, 79 and 87, what is the interquartile range?

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And here are the potential answers...

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We're given a bunch of test scores and we want to find the IQR, or interquartile range.

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Remember that the IQR is the distance between

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Q1 and Q3 in the five number summary of a set of data.

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As its name suggests, a five number summary... summarizes the data of 5 numbers.

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Those five numbers are: minimum, q1, median,

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q3, and maximum. It's obvious that minimum is the smallest,

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and maximum is the biggest. Not too far off is median, which is the middle

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value. Q1 is between the minimum and median, and Q3 is between the median and maximum.

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So, to find our IQR, we'll want to subtract Q1 from Q3.

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Since our data is only 5 values, it's easy to figure out the values we want for our 5

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number summary. Then, it's a simple matter of subtracting

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71 from 79 to get 8.

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The IQR is 8, so our answer is (E).

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