SOLUTION: Cathy scored 76, 84, and 78 on three tests. How much must she score on the next test to have at least an 80 average?

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Question 721522: Cathy scored 76, 84, and 78 on three tests. How much must she score on the next test to have at least an 80 average?
Answer by rfer(16322) About Me  (Show Source):
You can put this solution on YOUR website!
(76+84+78+x)/4=80
238+x=80*4
238+x=320
x=320-238
x=82