If Joe scored 25 on a test with a mean of 20 and a standard deviation of 5 what is his z-score?
A)25
B)+1.0
C)0.0
D)cannot be determined

Question

Quizplus · Accepted Answer

The z-score formula is:
z = (x - μ) / σ
where x is the value (in this case, Joe's score), μ is the mean, and σ is the standard deviation.

Substituting the given values:
z = (25 - 20) / 5
z = 1.0

Therefore, the z-score is +1.0, which corresponds to choice B.

If Joe Scored 25 on a Test with a Mean