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Question
NARRBEGIN: SA_101_104A real estate agency wants to compare the appraised values of single-family homes in two cities in Michigan. A sample of 60 listings in Lansing and 99 listings in Grand Rapids yields the following results (in thousands of dollars):
| Lansing | Big Rapids | |
 | 191.33 | 172.34 |
| s | 32.6 | 16.92 |
| n | 60 | 99 |
(A) Is there evidence of a significant difference in the average appraised values for single-family homes in the two Michigan cities? Use 0.05 level of significance.
(B) Have any of the assumptions made in (A) been violated? Explain.
(C) Construct a 95% confidence interval estimate of the difference between the population means of Lansing and Grand Rapids.
(D) Explain how to use the confidence interval in (C) to answer (A).
Answer
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NARRBEGIN: SA_79_80
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