1. The following data represent the daily supply (y in thousands of units) and the unit price (x in dollars) for a product. (25 pts) Daily Supply (y) Unit Price (x) 5 2 7 4 9 8 12 5 10 7 13 8 16 16 16 6 a. Compute the sample covariance for the above data. ANS: b. Compute the standard deviation for the daily supply. ANS: c. Compute the standard deviation for the unit price. ANS: d. Compute and interpret the sample correlation coefficient. ANS: 2. The Michael Painting Company has purchased paint from several suppliers. The purchase price per gallon and the number of gallons purchased are shown below. Supplier Price Per Gallon ($) Number of Gallons A 23 700 B 25 200 C 29 100 D 27 200 Compute the weighted average price per gallon. (25 pts.) ANS:
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Without the data, we cannot perform these calculations. Second, for the weighted average price per gallon, we need the actual prices per gallon from each supplier. The formula for the weighted average is: Show more…
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The following data represent the daily supply (y in thousands of units) and the unit price (x in dollars) for a product. Daily Supply (y) Unit Price (x) 5 2 7 4 9 8 12 5 10 7 13 8 16 16 16 6 a. Compute and interpret the sample covariance for the above data. b. Compute the standard deviation for the daily supply. c. Compute the standard deviation for the unit price. d. Compute and interpret the sample correlation coefficient.
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