SOLUTION: Brian has marks of 75,82 and 90 on three math tests. What mark must he obtain on the next test to have an average of exactly 85 for the four math tests.

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Question 1067682: Brian has marks of 75,82 and 90 on three math tests. What mark must he obtain on the next test to have an average of exactly 85 for the four math tests.
Answer by rfer(16322) About Me  (Show Source):
You can put this solution on YOUR website!
(75+82+90+x)/4=85
247+x=85*4
x=340-247
x=93