Question

A researcher wishes to determine the difference in two population means. To do this, she randomly samples 9 items from each population and computes a 90% confidence interval. The sample from the first population produces a mean of 780 with a standard deviation of 240. The sample from the second population produces a mean of 890 with a standard deviation of 280. Assume that the values are normally distributed in each population. The point estimate for the difference in the means of these two populations is _______.

Answer 1

-110

Step-by-step explanation:

The point estimate has been indicated which represents the difference between the mean of the first population and that of the second population.

Hence, point estimate = mean of the first population - mean of the second population

= 780 - 890

= -110