r1smith wrote:
In order to solve this problem, I found the mean of each set and then took the absolute value of the variances of each value in the set in relation to the mean. Then I added them all together to give me an estimate of the standard deviation. That looked something like this:
Set A mean = 7 —> 2, 6, 5, 0 ==> 13
Set B mean = 7.4 —> 1.6, 5.6, 3.4, 5.4, 1.6 = 17.6
Set C mean = 6.4 —> 2.6 , 6.6, 2.4, 4.4, 2.4 = 18.4
Set D mean = 6.8 —> 2.2 , 6.2 , 2.8 , 4.8 , 0.8 = 16.8
13 < 16.8 < 17.6 < 18.4
A < D < B < C ------> Answer Choice E
This is a standard approach that everyone would follow. I was hoping for something like estimation or any simplified methods.