Chapter 5.4, Problem 34E

Which Is More Likely? Assume that the carbon dioxide emissions in Exercise 32 are normally distributed. Are you more likely to randomly select 1 country with carbon dioxide emissions less than 30 metric tons or to randomly select a sample of 15 countries with mean carbon dioxide emissions less than 30 metric tons? Explain.

32. Carbon Dioxide Emissions The mean per capita carbon dioxide emissions in 58 industrialized countries over a 22-year period is 25.5 metric tons. A random sample of 44 countries is selected. What is the probability that the mean carbon dioxide emissions for the sample is greater than 28 metric tons? Assume σ = 395.1 metric tons. (Source: Energy Reports)