# Confidence interval estimation

A sample of 40 investment customers serviced by an acct manager are found to have had an average of #23,000 in transactions during the past year, with a standard deviation of $8,500. A sample of 30 customers serviced by another account manager averaged $28,000 in transactions, with a standard deviation of $11,000. Assuming the population standard deviations are equal, use the 0.05 level of significance in testing whether the population means could be equal for customers serviced by the two account managers. Using the appropriate statistical table, what is the most accurate statement we can make about the p-value for this test? Construct and interpret the 95% confidence interval for the difference between the population means.

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#### Solution Summary

The solution provides step by step method for the calculation of confidence interval . Formula for the calculation and Interpretations of the results are also included.