History: Florence Nightingale What was the age distribution of nurses in Great Britain at the time of Florence Nightingale? Thanks to Florence Nightingale and the British census of 1851, we have the following information (based on data from the classic text Notes on Nursing, by Florence Nightingale).

Note: In 1851 there were 25,466 nurses in Great Britain. Furthermore, Nightingale made a strict distinction between nurses and domestic servants.

Age range (yr) 20–29 30–39 40–49 50–59 60–69 70–79 80+

Midpoint x 24.5 34.5 44.5 54.5 64.5 74.5 84.5 Percent of nurses 5.7% 9.7% 19.5% 29.2% 25.0% 9.1% 1.8%

(a) Using the age midpoints x and the percent of nurses, do we have a valid probability distribution?

Explain.

(b) Use a histogram to graph the probability distribution of part (a).

(c) Find the probability that a British nurse selected at random in 1851 was 60 years of age or older.

(d) Compute the expected age m of a British nurse contemporary to Florence Nightingale.

(e) Compute the standard deviation s for ages of nurses shown in the distribution.

AppendixLO1