A social researcher has constructed a measure of racial prejudice and obtained a distribution of scores on this measure from a randomly selected sample of public office holders.The scores were normally distributed with a mean of 45 and a standard deviation of 7.What is the probability that a randomly selected case from the sample in the previous question would have a score of 52 or more?
A)0.7500
B)0.6826
C)0.3413
D)0.1587

Question

Quizplus · Accepted Answer

We need to calculate the z-score first:

z = (52-45)/7 = 1

Then, we find the probability of a z-score being greater than 1 using a table of standard normal probabilities or a calculator:

P(z > 1) = 0.1587

Therefore, the probability of a randomly selected case from the sample having a score of 52 or more is 0.1587 or approximately 0.16.

The correct answer is D.

A Social Researcher Has Constructed a Measure of Racial Prejudice