SOLUTION: A student has taken five test:84, 69, 78, 81 and 70. What would he have to make on the 6th test to have an average of 78.

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Question 827429: A student has taken five test:84, 69, 78, 81 and 70. What would he have to make on the 6th test to have an average of 78.
Answer by TimothyLamb(4379) About Me  (Show Source):
You can put this solution on YOUR website!
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(84 + 69 + 78 + 81 + 70 + x)/6 = 78
382 + x = 78*6
x = 78*6 - 382
x = 86
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