Question

Suppose that we have the data from 10 subjects and they reported their ages as the following: 19, 24, 31, 31, 54, 34, 62, 22, 45, 27. What is the standard deviation of this sample? (Round to two decimal places)

Answer 1

Answer)

19, 24, 31, 31, 54, 34, 62, 22, 45, 27

First we need to find the sample mean

Sample mean = (sum of the observations)/(number of observations)

Sample mean = (19+24+.....)/(10) = 34.9

Now we need to subtract this mean from each and every observation and then we need to take the square and add all the results

= (19-34.9)^2 + (24-34.9)^2....

= 1832.9

Now we need to divide 1832.9 by n-1 that is by 9

And take the square root

S.d = √{1832.9/9} = 14.2708 ~ 14.27