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Steve's scores on 6 of his tests were 92, 78, 86, 92, 95, and 91. If he took a seventh test and raised the mean of his scores by exactly 1 point, what was the score on the seventh test? Show your work.

User Grice
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1 Answer

5 votes

Answer:

96

Explanation:

First we need to know the mean of the Steve's scores on 6 of his tests. Given the six scores as 92, 78, 86, 92, 95, and 91.

Mean = sum of the scores/Total test taken

Mean = 92+78+86+92+95+ 91/6

Mean = 534/6

Mean = 89

If he took the seventh test and the mean score is raised by 1 them the new mean will be expressed as;

New mean = 92+78+86+92+95+ 91+x/7 = 89+1

Where x is the new score. Note that of a new score is added, the total year taken will also change to 7

To get x;

92+78+86+92+95+ 91+x/7 = 89+1

92+78+86+92+95+ 91+x/7 = 90

534+x/7 = 90

Cross multiply

533+x = 90×7

533+x = 630

x = 630-534

x = 96

Hence the score of the seventh test is 96

User Mikhail Kholodkov
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