SOLUTION: The mean of a three numbers is 10. Two of the numbers are 4 and 7. Find the third number.

Algebra ->  Percentage-and-ratio-word-problems -> SOLUTION: The mean of a three numbers is 10. Two of the numbers are 4 and 7. Find the third number.      Log On


   

Question 820660: The mean of a three numbers is 10. Two of the numbers are 4 and 7. Find the third number.
Answer by TimothyLamb(4379) About Me  (Show Source):
You can put this solution on YOUR website!
(4 + 7 + n)/3 = 10
4 + 7 + n = 30
11 + n = 30
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answer:
n = 19
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