ABSTRACT
The "average" of this population is known as the ''mean,'' whicb is often denoted by the Greek letter 11 (pronounced "mu"), orsometimes as the"50th Percentile."
Standard Davlllion =s = S.D. The standard deviation indicates the degree of spread of the
particular population away from the mean, often denoted by the Greek: letter a (pronounced "sigma'') or by the initials "S.D." Standard deviations are often used in estshlishing equipment design criteria to accommodate differences in people.
