Unit 1 Milestone - 8

A work measurement analyst at the Dorben Company took 10 observations of a high-production job. He rated the performance of each cycle and then calculated the average normal time for each item. The item with the largest dispersion had a mean of 0.30 minutes and a standard deviation of 0.03 minutes. If it is desired to have sample data within ±5% of the actual data, how many observations should the time study analyst take of this operation?

The data shown in Table 1 are the deviations from nominal diameter for holes drilled in a carbon-fiber composite material used in aerospace manufacturing. The values reported are deviations from nominal in ten-thousandths of an inch. (a) Set up and R charts on the process. Is the process in statistical control? (b) Estimate the process standard deviation using the range method. (c) If specifications are at nominal ±100, what can you say about the capability of this process? Calculate the PCR Cp Table 1. Hole Diameter Data Sample Number X1 X2 1 2 3 4 5 6 7 8 9 10 11 12 14 15 16 17 18 19 20 -30 +50 0 -50 -10 -10 +20 -40 0 0 -30 0 +20 0 0 +70 0 +10 +40 +30 +30 +30 +10 0 +20 +50 +50 -20 +50 -60 +10 0 0 +20 +10 -20 -10 0 +20 X3 X4 X5 -30 +20 +30 +50 +40 +20 +30 +20 +30 +20 +30 0 +20 +10 +40 +10 +10 -10 +50 -10 -30 -10 +50 +40 0 +30 -10 0 +30 +30 -20 +50 +30 +10 +40 +20 0 +30 +10 +30 -20 +30 +30 +20 -20 +50 +20 +10 -40 +20 -20 -10 -10 0 -20 +10 +10 +50 0 +10

A hotel chain based in the United States contracts with a European vacuum cleaner manufacturer to supply a large number of upright cleaner units. After delivery, the hotel raises questions about manufacturer vacuum cleaner performance claims, pointing out that the units should have been tested to meet ASTM 558, an American standard. The manufacturer notes the advertised performance is based on IEC 60312, a European standard, and the two test codes will yield similar, if not exact, results. Investigate both test codes and address similarities and differences. Is there a legitimate claim here?

Fill in the blanks: On a particular day a random sample of 12 tins of peas is taken from the output of a canning factory and their contents are weighed. The mean and standard deviation of the weight for the sample are 301.8 gm and 1.8 gm respectively. Find 99% confidence limits for the mean weight of peas in tins produced by the factory on the day in question. use 3 decimal places E = Lower limit? Upper limit?

Bolts installed on a production line are tightened with automatic wrenches. They are to be tightened sufficiently to yield the full cross-section in order to produce the highest possible initial tension. The limiting condition is twisting off the bolt head during assembly. The bolts have a mean twisting off torque of 20 Nm with a standard deviation of 1 Nm. The automatic wrenches have a standard deviation of 1.5Nm. What mean value of torque wrench setting would result in only 1 in 500 twisting off during assembly? Give a rough estimate only. A unit has a constant failure rate of 0.3% per 1000 hours. What is its MTBF? What are the probabilities of the unit successfully completing missions of 10000, 100000 and 1000000 hours? Give a rough estimate only.

Five of your classmates measured the diagonal length of the blackboard. Classmate A measured it as 2.54 m; classmate B as 2.46 m; classmate C as 2.65 m; classmate D as 2.55 m; and classmate E as 2.39m. Find the variance and standard deviation of the measurements. Also, express the average measurement in a form that includes uncertainty.

1. A sample of 169 is drawn from a certain population. This sample has a mean of 80 and a standard deviation of 10. Find the standard error of the mean.

Testing and Rework Bolts installed on a production line are tightened with automatic wrenches. They are to be tightened sufficiently to yield the full cross-section in order to produce the highest possible initial tension. The limiting condition is twisting off the bolt head during assembly. The bolts have a mean twisting off torque of 20 Nm with a standard deviation of 1 Nm. The automatic wrenches have a standard deviation of 1.5Nm. What mean value of torque wrench setting would result in only 1 in 500 twisting off during assembly? Give a rough estimate only. A unit has a constant failure rate of 0.3% per 1000 hours. What is its MTBF? What are the probabilities of the unit successfully completing missions of 10000, 100000 and 1000000 hours? Give a rough estimate only. Please provide an in depth answer for the above questions, thank you so much!

1.Calculate Mean ,Median ,standard deviation and variance for measurement sets A, B and C SET A :398 ,420, 394, 416, 404, 408 ,400, 420 ,396, 413 ,430. • SET B:409 406 402 407 405 404 407 404 407 407 408 SET C:409 406 402 407 405 404 407 404 407 407 408 406 410 406 405 408 406 409 406 405 409 406 407

A new electronic component for aircraft is tested to withstand temperatures as low as -50°F. One engineer suggests that the device cannot actually stand temperatures that low. What are the Type I and Type II errors? Type I: The device CAN NOT withstand temperatures as low as -50F but the engineer incorrectly finds that it CAN.Type II: The device CAN withstand temperatures as low as -50F but the engineer incorrectly finds that it CAN NOT.   Type I: The device CAN withstand temperatures as low as -50F but the engineer incorrectly finds that it CAN NOT.Type II: The device CAN NOT withstand temperatures as low as -50F but the engineer incorrectly finds that it CAN.    Is the answer the first or second bullet point?

answer all parts

Installation of a certain hardware takes a random amount of time with a standard deviation of 5 minutes. A computer technician installs this hardware on 64 different computers, with the average installation time of 42 minutes. Compute a 95% confidence interval for the mean installation time. (1 decimal place) Lower limit = || Upper limit =

Sam's Long Life 75-watt light bulbs are designed to have a life of 1,150 hours with tolerances of ±205 hours. The process that makes light bulbs has a mean of 1,040 hours, with a standard deviation of 55 hours. Compute the process capability ratio and the process capability index, and comment on the overall capability of the process. (Round answers to 2 decimal places, e.g. 2.75.)

"The temperature of an ice bath is measured numerous times with a digital thermometer. The true temperature of the ice bath is 0.07202C. The sample mean temperature is T = -0.0008C. The sample standard deviation of all the readings is 0.02529C. We assume that the precision errors in the readings are purely random. In the standard engineering format, calculate the tolerance for 95%."