3. The manager of a building-supplies company randomly samples incoming lumber to see whether it meets quality specifications. From each shipment, 100 pieces of 2 x 4 lumber are inspected and judged according to whether they are first (acceptable) or second (defective) grade. The proportions of second-grade 2 x 4s recorded for 30 shipments were as follows: a. Construct a control chart for the proportion of second-grade 2 x 4s in samples of 100 pieces of lumber. b. Explain how the control chart can be of use to the manager of the building supplies company. Shipment No. Proportion of second grade 1 0.14 2 0.22 3 0.21 4 0.15 5 0.19 0.26 7 0.18 8 0.22 9. 0.23 10 0.21 11 0.2 12 0.14 13 0.25 14 0.2 15 0.19 16 0.18 17 0.22 18 0.22 19 0.17 20 0.21 21 0.21 22 0.13 23 0.15 24 0.2 25 0.23 26 0.23 27 0.12 28 0.19 29 0.19 30 0.26

3. The manager of a building-supplies company randomly samples incoming lumber to see whether it meets quality specifications. From each shipment, 100 pieces of 2 x 4 lumber are inspected and judged according to whether they are first (acceptable) or second (defective) grade. The proportions of second-grade 2 x 4s recorded for 30 shipments were as follows: a. Construct a control chart for the proportion of second-grade 2 x 4s in samples of 100 pieces of lumber. b. Explain how the control chart can be of use to the manager of the building supplies company. Shipment No. Proportion of second grade 1 0.14 2 0.22 3 0.21 4 0.15 5 0.19 0.26 7 0.18 8 0.22 9. 0.23 10 0.21 11 0.2 12 0.14 13 0.25 14 0.2 15 0.19 16 0.18 17 0.22 18 0.22 19 0.17 20 0.21 21 0.21 22 0.13 23 0.15 24 0.2 25 0.23 26 0.23 27 0.12 28 0.19 29 0.19 30 0.26

Practical Management Science

6th Edition

ISBN:9781337406659

Author:WINSTON, Wayne L.

Publisher:WINSTON, Wayne L.

Chapter2: Introduction To Spreadsheet Modeling

Section: Chapter Questions

Problem 20P: Julie James is opening a lemonade stand. She believes the fixed cost per week of running the stand...

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