The average of 5 numbers is 23. If the average of 4 of these numbers is 25, what is the fifth number?
The average of 5 numbers is 23. If the average of 4 of these numbers is 25, what is the fifth number?
Explanation
The sum of the 5 numbers is:
5 × 23 = 115
The sum of the 4 numbers is:
4 × 25 = 100
The fifth number is:
115 - 100 = 15