Question

The ASQ​ (American Society for​ Quality) regularly conducts a salary survey of its​ membership, primarily quality management professionals. Based on the most recently published mean and standard​ deviation, a quality control specialist calculated the​z-score associated with his own salary and found it was minus2.50. What is his​ salary?

A. 2.5 standard deviations below the average salary.

B. 2 and a half times less than the average salary.

C. 2.5 standard deviations above the average salary.

D. 2 and a half times more than the average salary.

Answer 1

A. 2.5 standard deviations below the average salary.

Explanation:

In a normally distributed sample, the z-score measure how many standard deviations a measure is above or below the mean.

If the zscore is positive, the measure is above the mean.

If it is negative, the measure is below the mean.

A quality control specialist calculated the​z-score associated with his own salary and found it was minus2.50. What is his​ salary?

This means that his salary is 2.5 standard deviations below the mean, that is the average salary.

The correct answer is A.