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 _______.
A)-110
B)40
C)-40
D)0
E)240

Question

Quizplus · Accepted Answer

The point estimate for the difference in the means of two populations is found by subtracting one sample mean from the other. Here, it's 780 - 890 = -110.

A Researcher Wishes to Determine the Difference in Two Population