A population of scores has µ = 44.In this population,a score of X = 40 corresponds to z = -0.50.What is the population standard deviation?
A)2
B)4
C)8
D)-8

Question

A population of scores has µ = 44.In this population,a score of X = 40 corresponds to z = -0.50.What is the population standard deviation?​
A)2​
B)​4
C)​8
D)​-8

Quizplus · Accepted Answer

From the given information, we know:

z = (X - µ) / σ

where z is the z-score, X is the raw score, µ is the population mean, and σ is the population standard deviation.

We are given that µ = 44, X = 40, and z = -0.50. Substituting these values into the above formula, we get:

-0.50 = (40 - 44) / σ

Solving for σ, we get:

σ = (4) / 0.50 = 8

Therefore, the population standard deviation is 8, so the answer is choice C.

A Population of Scores Has µ = 44