njosh

Answer all questions. Partial credit is possible. Round to 2 decimal places for all answers . Please don’t try to do this by hand. Use Excel, as demonstrated in class.

1. A.) If one country is selected randomly from this data set, what is the probability that its population will be less than 50 million? ________________.

B.) If one country is selected randomly from this data set, what is the probability that its population will be less than 25 million given that it is from North Africa? ________________.

C.) If one country is selected randomly from this data set, what is the probability that its GDP will be less than $100 billion? ________________.

D.) If one country is selected randomly from this data set, what is the probability that its GDP be less than $50 billion given that it is from Africa? ________________.

2. Calculate the mean per capita GDP in each subgroup. There should be 15 such means. Then assuming that they represent a random sample of countries from the global economy, construct the 95% confidence interval for the mean per capita GDP for the world based on this sample. (Show all work in the space below. We are playing fast and loose with the rules with this method, but ignore that).

Recall the formula for the CI of the mean is: ± t. where = s/

Hint: You have to calculate the standard deviation of the 15 means using Excel for s.