One year, the mean age of an inmate on death row was 38.4 years. a sociologist wondered whether the mean age of a death-row inmate has changed since then. she randomly selects 32 death-row inmates and finds that their mean age is 36.4, with a standard deviation of 8.1. construct a 95% confidence interval about the mean age. what does the interval imply?

95% Confidence interval:  (33.48,39.32)

Step-by-step explanation:

We are given the following in the question:

Population mean, μ =  38.4 years

Sample mean, = 36.4 years

Sample size, n = 32

Alpha, α = 0.05

Sample standard deviation, s = 8.1 years

95% Confidence interval:  

Putting the values, we get,  

Since the mean age age that is 38.4 years belongs to this 95% interval, there is enough evidence to say that the mean age  of an inmate on death row has not changed.