If the standard deviation of 5, 7, 9, .... 151 is $$\sigma$$, then the standard deviation of 32, 44, 56. .... 908 is

Here,

Series 1 is an Arithmetic Progression with common difference = 2

Series 2 is an Arithmetic Progression with common difference = 12

Thus, Series 2 has common difference 6 times of the first.

Also, both the series have same no. of terms 

   Series 1 = (151-5)/D = (146)/2 = 73

   Series 2 = (908 - 32)/D = (876/12)= 73

Therefore , the Standard deviation of the second series will be 6 times of the first.

Hence,  6$$\sigma\ $$    Ans.