Question

Consider an x distribution with standard deviation σ = 36.

(a) If specifications for a research project require the standard error of the corresponding x distribution to be 3, how large does the sample size need to be?
n =  

(b) If specifications for a research project require the standard error of the corresponding x distribution to be 1, how large does the sample size need to be?
n =

Answer 1

Solution:

Given that

σ = 36

Let n be the sample size

We know that , the standard error is given by

S.E. =  

1)

Here ,

S.E. = 3

= 3

36/n = 3

n = 12

n = 144

2)

Here ,

S.E. = 1

= 1

36/n = 1

n = 36

n = 1296