SOLUTION: the average of 8 numbers is 25.after one of the numbers is removed,the average of the remaining numbers is 31.what number has been removed?

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Question 813376: the average of 8 numbers is 25.after one of the numbers is removed,the average of the remaining numbers is 31.what number has been removed?
Found 2 solutions by richwmiller, TimothyLamb:
Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
8*25=200
7*31=217
The total of the numbers is larger after a number was removed. Something is wrong.


Answer by TimothyLamb(4379) About Me  (Show Source):
You can put this solution on YOUR website!
a = 25
S = 25 * 8 = 200
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(S - n)/7 = 31
(200 - n)/7 = 31
200 - n = 217
n = 200 - 217
n = -17
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Answer:
the removed number is -17
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