Calculating Average Test Scores

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Sarah took eight math tests over the course of a semester. The table below shows her scores for each test:

Test Number	Score (out of 100)
1	85
2	92
3	78
4	88
5	95
6	83
7	90
8	89

Question

What is Sarah’s average (mean) test score for the semester?

To calculate the average (mean) test score, we need to:

Find the sum of all the scores
Divide the sum by the number of tests

Sum of all scores: 85 + 92 + 78 + 88 + 95 + 83 + 90 + 89 = 700

Number of tests: 8

Average score = 700 ÷ 8 = 87.5

Therefore, Sarah’s average test score for the semester is 87.5 out of 100.

Alternative method: We could also think of this as a fair share problem. If we wanted to distribute the total points (700) equally among the 8 tests, we would end up with 87.5 points per test.