According to the center for disease control and prevention (cdc), the mean life expectancy in 2015 for non‑hispanic black males was 71.8 years.
assume that the standard deviation was 15 years, as suggested by the bureau of economic research. the distribution of age at death, is not normal because it is skewed to the left. nevertheless, the distribution of the mean, ⎯⎯⎯, in all possible samples of size is approximately normal if is large enough, by the central limit theorem. let ⎯⎯⎯ be the mean life expectancy in a sample of 100 non‑hispanic black males.
determine the interval centered at the population mean such that 95% of sample means ⎯⎯⎯ will fall in the interval.
give your answers precise to one decimal. you may need to use software or a table of critical values.