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QUESTION 5 20 points Save Answer Installing a muffler at Barut Garage, Inc. involves a live work lasks. Azra has timed workers performing these lasks seven imes, with the resulls (in minules) shown in the following table. tS ect correct mflers 各 Xi 3I Complete 5 paperwork | 8 |9 | 10 | 9 | 10 | 8 | 85 Given that Azra does not want an error of more than 0.08 and a confidence level less than 0.30 answer the following Provide thez Does the number of observations for the following tasks amant such confidence level? Round to the nearest hundrecth, for example 4.22 Enter YES I ask # 3 install new muffler Task # 5 Complete paperwork What are the required numbers of observations for these tasks? Enter the number Task # 3 install new muffler Task # 5 Complete paperwork or NO
Expert Answer
Z score at 90% confidence level = 1.65
| No. | Task | 1 | 2 | 3 | 4 | 5 | 6 | 7 | Sample Average (A) |
Sample SD (s) |
Error level (e ) |
Z | n =(z.s / e.A)^2 |
| 3 | Install new muffler | 13 | 11 | 11 | 12 | 14 | 13 | 14 | 12.5714286 | 1.27241802 | 0.08 | 1.65 | 4.357910156 |
| 5 | Complete paperwork | 9 | 8 | 9 | 10 | 9 | 10 | 8 | 9 | 0.81649658 | 0.08 | 1.65 | 3.501157407 |
| No. | Task | 1 | 2 | 3 | 4 | 5 | 6 | 7 | Sample Average (A) |
Normal Time N=A x PR |
Standard Time S=N x (1.15) |
| 2 | Remove old muffler | 8 | 5 | 7 | 5 | 7 | 5 | 8 | 6.42857143 | 7.71428571 | 8.871428571 |
| 4 | Inspect the work | 4 | 3 | 4 | 3 | 4 | 4 | 3 | 3.57142857 | 3.92857143 | 4.517857143 |
| No. | Task | 1 | 2 | 3 | 4 | 5 | 6 | 7 | Sample Average (A) |
Normal Time N=A x PR |
Standard Time S=N x (1.15) |
| 1 | Select correct muffler | 3 | 3 | 6 | 3 | 5 | 3 | 3 | 3.71428571 | 3.15714286 | 3.630714286 |
| 2 | Remove old muffler | 8 | 5 | 7 | 5 | 7 | 5 | 8 | 6.42857143 | 7.71428571 | 8.871428571 |
| 3 | Install new muffler | 13 | 11 | 11 | 12 | 14 | 13 | 14 | 12.5714286 | 13.8285714 | 15.90285714 |
| 4 | Inspect the work | 4 | 3 | 4 | 3 | 4 | 4 | 3 | 3.57142857 | 3.92857143 | 4.517857143 |
| 5 | Complete paperwork | 9 | 8 | 9 | 10 | 9 | 10 | 8 | 9 | 7.65 | 8.7975 |
| 41.720357 |
