Question

at the end of last year, the legal arm of a large commercial airline issued a document that included statements about the flight experience of the airline’s pilots (the total flying time per pilot). to check these statements, a federal watchdog organization examined the flight records of a random sample of 30 of the airline’s pilots. the pilots in the sample, as of the end of last year, had a sample mean experience of 3214 hours with a sample variance of 85,292 hours². the airline’s document stated that, at the end of last year, the airline’s pilots had a population mean experience of 3345 hours of flight with a population variance of 84,324 hours². fill in the blanks below with the proper notation for the population mean, the sample mean, and the sample variance. population mean: select = 3345 hours sample mean: select = 3214 hours sample variance: select = 85,292 hours²

Explanation:

Step1: Recall Notation for Population Mean

The population mean is denoted by the Greek letter mu, $\mu$. The airline's stated population mean is 3345 hours, so the notation for population mean is $\mu$.

Step2: Recall Notation for Sample Mean

The sample mean is denoted by $\bar{x}$ (x - bar). The sample mean from the 30 pilots is 3214 hours, so the notation for sample mean is $\bar{x}$.

Step3: Recall Notation for Sample Variance

The sample variance is denoted by $s^2$. The sample variance from the sample is 85292 hours², so the notation for sample variance is $s^2$.

Answer:

Population mean: $\boldsymbol{\mu}$ = 3345 hours
Sample mean: $\boldsymbol{\bar{x}}$ = 3214 hours
Sample variance: $\boldsymbol{s^2}$ = 85292 hours²