Answer:
3.28
Step-by-step explanation:
find the mean of all the numbers
3 + 8 + 10 + 12 + 15 = 48
48/5=9.6
so the mean of all the numbers is 9.6
now subtract 9.6 from all the numbers
|3 - 9.6| = 6.6
|8 - 9.6| = 1.6
|10 - 9.6| = .4
|12 - 9.6| = 2.4
|15 - 9.6| = 5.4
Find the mean/average of the new values
6.6 + 1.6 + .4 + 2.4 + 5.4 = 16.4
16.4/5 = 3.28