Answer
Part A
i) z $\approx$ 1.34
ii) z $\approx$ -0.82
iii) z $\approx$ 2.22
iv) z $\approx$ -0.34
Part B
$x$ = 2200 is an unusual value
Work Step by Step
Part A
Use the formula z = $\frac{x - \mu}{\sigma}$ to convert $x$ values to z scores.
i) z = $\frac{1920 - 1498}{316}$ $\approx$ 1.34
ii) z = $\frac{1240 - 1498}{316}$ $\approx$ -0.82
iii) z = $\frac{2200 - 1498}{316}$ $\approx$ 2.22
iv) z = $\frac{1390 - 1498}{316}$ $\approx$ -0.34
Part B
$x$ = 2200 is an unusual value because it is more than two standard deviations (as seen by its z score of 2.22) away from the mean.
