What is the probability that someone who died of coronary heart disease between the ages of 75 and 84 was a smoker?

Assignment

In a 1985 study, Breslow (cited in Hand et al., 1994) examined the death rates from coronary heart disease in a set of British male physicians. He also classified the doctors according to whether or not they smoked cigarettes. The table below shows the number of physicians who died from coronary heart disease.

Age, smoking, and heart disease in a sample of male physicians

Age (in years) Nonsmokers Smokers
35-44 2 32
45-54 12 104
55-64 28 206
65-74 28 186
75-84 31 102

Use the data to answer the following questions:

How many doctors were surveyed?

How many of these doctors reported that they smoked? How many reported that they did not smoke?

What is the probability that a person who died of coronary heart disease was between the ages of 35 and 44? Within this age group (i.e., 34 to 44), what is the probability that the person was a smoker?

What is the probability that someone who died of coronary heart disease between the ages of 75 and 84 was a smoker?

At what age range from the table above is smokers the highest proportion of those who died from coronary heart disease?