First find the mean (sum divided by number of values)
4+5+8+10+15=42
42/5=8.4
Then find the difference between each of the numbers and the mean.
4.4, 3.4, 0.4, 1.6, 6.6
Then find the mean of those values.
4.4+3.4+0.4+1.6+6.6=16.4
16.4/5=3.28
Final answer: 3.28
2/3 , 3/4 7/12 there you go
Hopefully this helps you !
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