SOLUTION: The mean of five numbers is 12 . If the first four numbers are 7,9,10 and 13 , find the fifth number .

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Question 748630: The mean of five numbers is 12 . If the first four numbers are 7,9,10 and 13 , find the fifth number .
Answer by Cromlix(4381) About Me  (Show Source):
You can put this solution on YOUR website!
If the mean of 5 numbers is 12
then the full total must = 5 x 12 = 60
Adding up the given numbers 7,9,10 and
13 totals 39.
Therefore the missing number must be
60 - 39 = 21.