Mean, median, mode, and range

Recall how to find the average of a set of numbers:

Thus, we can write the following to solve for the average of Kim's test scores:

Kim has a as her test score average.

To find the median of a group of scores, first, arrange the scores from least to greatest:

There are an even number of scores, so the median is the mean of the two scores that fall in the middle, which are noted in red above. Add the scores and divide by two:

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