What is the z-score of X, if n = 204, mu= 15μ=15, SD =1, and X =35? Statistics Inference with the z and t Distributions One-sample z test 1 Answer Bill K. Feb 8, 2016 z=(X-mu)/(SD)=(35-15)/1=20 is the z-score of X itself. If you want the z-score of a mean overline{X}=35, the answer is z=(overline{X}-mu)/((SD)/sqrt(n))=20/(1/sqrt(204)) approx 285.7. Such high z-scores rarely occur in real life examples. Answer link Related questions What does a z-test measure? What type(s) of distributions can a z-test be applied to? How do you calculate a z-score? What is the z-score of X, if n = 25, mu= 60, SD = 12, and X =58? What is the z-score of X, if n = 135, mu= 70, SD = 1, and X =75? What is the z-score of X, if n = 135, mu= 74, SD =3, and X =73? What is the z-score of X, if n = 4, mu= 60, SD =3, and X =60? What is the z-score of X, if n = 3, mu= 55, SD =2, and X =56? What is the z-score of X, if n = 57, mu= 35, SD =5, and X =13? What is the z-score of X, if n = 72, mu= 137, SD =25, and X =13? See all questions in One-sample z test Impact of this question 2479 views around the world You can reuse this answer Creative Commons License