A social work researcher constructed a measure of quality of life and obtained a distribution of scores on this measure from a randomly selected sample of elderly persons. 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 will have a score less than 38?
A) 0.5200
B) 0.5018
C) 0.4526
D) 0.1587

Question

Quizplus · Accepted Answer

The Z-score for a score of 38 is (38-45)/7 = -1. The probability of a Z-score being less than -1 in a standard normal distribution is approximately 0.1587.

A Social Work Researcher Constructed a Measure of Quality of Life