If your sample mean is 30, your population average is 10, and your standard error of the mean is 5, what is your observed z value?
A)6
B)−2.5
C)4
D)20

Question

Quizplus · Accepted Answer

The observed z-value would measure how many standard errors the sample mean is from the population mean.

z = (sample mean - population mean) / standard error

z = (30 - 10) / 5

z = 4

Therefore, the observed z-value is 4, which corresponds to choice C.

If Your Sample Mean Is 30, Your Population Average Is