Question

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	5.9%	9.6%	19.4%	29.5%	24.9%	8.7%	2.0%

(c) Find the probability that a British nurse selected at random in 1851 would be 60 years of age or older. (Round your answer to three decimal places.)


(d) Compute the expected age μ of a British nurse contemporary to Florence Nightingale. (Round your answer to two decimal places.)
yr

(e) Compute the standard deviation σ for ages of nurses shown in the distribution. (Round your answer to two decimal places.)
yr

Answer 1

(c) The the probability that a British nurse selected at random in 1851 would be 60 years of age or older is ,

P(60 years of age or older)=24.9%+8.7%+2%=35.6%

(d) The expected age μ of a British nurse contemporary to Florence Nightingale is ,

yr

(e) The  standard deviation σ for ages of nurses shown in the distribution is ,

yr

Therefore ,

yr