Aresearcher 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

-110

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  

this statement is true.

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