Find the missing number when you know the mean
Find the total from the mean, then subtract the numbers you know.
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The mean of 5 numbers is 22. 4 of the numbers are 5, 29, 29, 29. What is the other number?
Answer: 18
The mean of 5 numbers is 18. 4 of the numbers are 30, 10, 22, 22. What is the other number?
Answer: 6
The mean of 5 numbers is 16. 4 of the numbers are 9, 8, 25, 12. What is the other number?
Answer: 26
Tip: Find the total from the mean, then subtract the numbers you know.
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