Forecasts almost always contain errors

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Forecasts almost always contain errors.

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Q: A bank randomly looks at loan applications and checks them for errors. Ten applications and the number of errors identified on the applications are found in the following table. When the process is working correctly, the average number of errors found is 2. Construct a c-chart to determine if the process is in control. Application number Number of errors 1 3 2 0 3 1 4 0 5 3 6 2 7 4 8 4 9 1 10 1

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Q: SimQuick is to be used to simulate the following bank process: Customers arrive at the Entrance Door of the bank with an average time between arrivals of 2.5 minutes. The Line Buffer holds 6 customers. If a customer arrives and the buffer line is filled, the customer leaves. The Work Station Teller's processing time per customer is normally distributed, with a mean of 3.0 minutes and a standard deviation of 0.5 minutes. The Served Customer Buffer in the flowchart is used to count the number of customers processed during the simulation period. A 2-hour period is to be simulated and the simulation should be repeated 30 times. Determine: a) The number of customers served during the 2-hour period; b) The percentage of customers who arrived at the bank and left because the buffer line was full; c) The utilization of the teller (% of time working) during the 2-hour period;

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Q: Construct a 3-sigma and R-chart for the length in centimeters of a part from the following table. Sample # Observation 1 Observation 2 Observation 3 Observation 4 1 0.486 0.499 0.493 0.511 2 0.499 0.506 0.516 0.494 3 0.496 0.5 0.515 0.488 4 0.495 0.506 0.483 0.487 5 0.472 0.502 0.526 0.469 6 0.473 0.495 0.507 0.493 7 0.495 0.512 0.49 0.471 8 0.525 0.501 0.498 0.474 9 0.497 0.501 0.517 0.506 10 0.495 0.505 0.516 0.511

Q: The three-person crew worked their way through the neighborhood, testing doorknobs and windows and slipping past security systems like a team of ninjas. Of course, they weren't ninjas, but a crew of brazen burglars, hoping to grab cash and other valuables to fence at the next level of their supply chain. Fortune smiles on them on this day in the prestigious Edmond Oaks neighborhood. A lawn maintenance crew is creating a tremendous racket mowing and edging lawns, which completely drowns out the sounds of breaking glass. Details of the day's haul appear in Table C. a. What is the multifactor productivity? b. What is the labor productivity? Table C: The Haul ITEM SALES PRICE LABOR MATERIAL Krugerrand $1,500 1 hr $2 Flat screen TV $250 .25 $1 $200 cash $200 .05 $45 Lava lamp $5 .15 $25 Rolex watch $180 .10 $1 Workers are paid at a flat rate of 20% of the sales price of the merchandise. Materials cost represents the cost of gasoline and surgical gloves, and overhead is 20% of the sales price of the merchandise.

Q: Consider this list of jobs that have just arrived and are ready for processing. They all require processing first on machine 1 and then on machine 2. Both machines are now idle. Develop a schedule that minimizes makespan and calculate this makespan time. Now assume that each job can be split into two jobs, each having half the duration on both machine 1 and machine 2. Using the original sequence that minimized average flow time, calculate the flow times for all split jobs What is the effect of this new schedule on the average flow time for these split jobs? Job Machine 1 Machine 2 1 14 6 2 11 12 3 16 14 4 12 8 5 22 9 6 13 15 7 10 12 8 8 13

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