Answer:
He needs 92 on his last test.
Step-by-step explanation:
Mean score:
The mean is the sum of all scores divided by the number of tests.
In this question:
Scores of 85, 89, 85, 89 and x(the last one).
5 tests.
We want a mean of 88. So we find x for a mean of 88.
[tex]\frac{85 + 89 + 85 + 89 + x}{5} = 88[/tex]
[tex]348 + x = 440[/tex]
[tex]x = 440 - 348 = 92[/tex]
He needs 92 on his last test.