What is the z-score of X, if n = 4, #mu= 60#, SD =3, and X =60?

1 Answer
Nov 12, 2015

Answer:

#z=0#

Explanation:

I have my own doubt about the correctness of the problem.

The sample size is #5#. It is appropriate to find #t# score.

#z# score shall be calculated only when the sample size is #>=30#
Some statisticians, if they believe the population distribution is normal, use #z# score even if the sample size is less than 30.

You didn't state explicitly for which distribution you want to compute #z#. It may be an observed distribution or it may be a sampling distribution.

Since you have asked the question, I shall answer by assuming it is a sampling distribution.

#SE = (SD)/sqrtn=3/sqrt4=3/2=1.5#

#z=(x-mu)/(SE)=(60-60)/1.5=0/1.5=0#

Note: If the Value of #X# is equal to Mean i.e., #mu# the #z# score is always 0.