Question

A student researcher compares the heights of American students and non-American students from the student body of a certain college in order to estimate the difference in their mean heights. A random sample of 18 American students had a mean height of 70.8 inches with a standard deviation of 2.69 inches. A random sample of 12 non-American students had a mean height of 63.4 inches with a standard deviation of 3.05 inches. Determine the 95% confidence interval for the true mean difference between the mean height of the American students and the mean height of the non-American students. Assume that the population variances are equal and that the two populations are normally distributed.

Step 1 of 3 :  

Find the point estimate that should be used in constructing the confidence interval.

Answer 1