Question

What is the z-score of sample X, if `n = 196, mu= 55, St. Dev. =42, and mu_X =58`?

Answer 1

`z=0.75`

Explanation:

Given -

`n=196`
`mu=55`
`SD=42`
`mu_x=58`
Find Standard error
`SE =sigma/sqrt(n)=42/sqrt(196)=42/14=3`
Calculate `z` score
`z=(mu-mu_x)/(SE)=(55-58)/4=-3/4=-0.75`