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Question
NARRBEGIN: SA_81_82A real estate agent has collected a random sample of 40 houses that were recently sold in Grand Rapids, Michigan. She is interested in comparing the appraised value and recent selling price (in thousands of dollars) of the houses in this particular market. The values of these two variables for each of the 40 randomly selected houses are shown below.
| House | Value | Price | House | Value | Price |
| 1 | 140.93 | 140.24 | 21 | 136.57 | 135.35 |
| 2 | 132.42 | 129.89 | 22 | 130.44 | 121.54 |
| 3 | 118.30 | 121.14 | 23 | 118.13 | 132.98 |
| 4 | 122.14 | 111.23 | 24 | 130.98 | 147.53 |
| 5 | 149.82 | 145.14 | 25 | 131.33 | 128.49 |
| 6 | 128.91 | 139.01 | 26 | 141.10 | 141.93 |
| 7 | 134.61 | 129.34 | 27 | 117.87 | 123.55 |
| 8 | 121.99 | 113.61 | 28 | 160.58 | 162.03 |
| 9 | 150.50 | 141.05 | 29 | 151.10 | 157.39 |
| 10 | 142.87 | 152.90 | 30 | 120.15 | 114.55 |
| 11 | 155.55 | 157.79 | 31 | 133.17 | 139.54 |
| 12 | 128.50 | 135.57 | 32 | 140.16 | 149.92 |
| 13 | 143.36 | 151.99 | 33 | 124.56 | 122.08 |
| 14 | 119.65 | 120.53 | 34 | 127.97 | 136.51 |
| 15 | 122.57 | 118.64 | 35 | 101.93 | 109.41 |
| 16 | 145.27 | 149.51 | 36 | 131.47 | 127.29 |
| 17 | 149.73 | 146.86 | 37 | 121.27 | 120.45 |
| 18 | 147.70 | 143.88 | 38 | 143.55 | 151.96 |
| 19 | 117.53 | 118.52 | 39 | 136.89 | 132.54 |
| 20 | 140.13 | 146.07 | 40 | 106.11 | 114.33 |
(A) Use the sample data to generate a 95% confidence interval for the mean difference between the appraised values and selling prices of the houses sold in Grand Rapids.
(B) Interpret the constructed confidence interval fin (A) for the real estate agent.
Answer
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