A normal distribution has mean μ = 16 and standard deviation σ = 3. Find and interpret the z-score for x = 13.
A) z = -3: a value of 13 is one standard deviation below the mean.
B) z = 19: a value of 13 is one standard deviation above the mean.
C) z = 1: a value of 13 is one standard deviation above the mean.
D) z = -1: a value of 13 is one standard deviation below the mean.

Question

Quizplus · Accepted Answer

The formula for z-score is z = (x - μ) / σ. Plugging in the values given, we get z = (13 - 16) / 3 = -1. This means that the value of 13 is one standard deviation below the mean. Therefore, the best choice is D.

A Normal Distribution Has Mean μ = 16 and Standard