A sociologist wants to determine if the life expectancy of p

A sociologist wants to determine if the life expectancy of people in Africa is less than the life expectancy of people in Asia. The data obtained is shown in the table below. Africa Asia Xbar1 = 63.3 yr. Xbar2 = 65.2 yr. 1 = 9.1 yr. 2 = 7.3 yr. n1= 120 n2 = 150 Calculate the critical value. Use = 0.05. -1.65 -2.33 -2.58 -1.96

Solution

As this is a LEFT TAILED TEST (by the phrase \"less than\"), then at 0.05 level, the critical value, by table/technology, is

zcrit = -1.65 [ANSWER]