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.

A. 2.5 standard deviations below the average salary.

Step-by-step 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.