Business Finance Homework Help

HW06. Reliability

Name: ________________________

• Please submit the assignment by the end of 03/15.
• Please show the steps. For Excel formula, please copy and paste the last Excel formula that was used to find out the solution.
• Attach the Excel file as a reference.
• Please do not say, “refer to the Excel file”.

• A manufacturing process is aiming for a nominal of 78 ounces with the tolerance of 1. Historically, the cost penalty when the process is out of control, was approximately $7.80 each unit. Based on the information and the table below, please calculate the following:
• Two processes, P and Q, are used by a supplier to produce the same component, Z, which is a critical part in the engine of the BearingPort 778 airplane. The specification for Z calls for a dimension of 0.24 mm ± 0.03. The probabilities of achieving the dimensions for each process based on their inherent variability are shown in the table found in the worksheet tab Prob. 7-16 in the Excel file C07Data. If k = 60,000, what is the expected loss for each process? Which would be the best process to use, based on minimizing the expected loss?
• The life of a Supercellular phone battery is normally distributed with a mean of 950 days and standard deviation of 40 days. Using the Excel functions (see Chapter 6), determine the following:

• the expected value of the quality dimension, that is E(x);
• the variance of the quality dimension, that is Var(x);
• the expected deviation of the quality dimension (the difference between the expected value and the nominal), and E(D) = E(x) – T
• the expected loss of the process per unit, that is EL.

Table 4.1 Quality Dimensions and their Frequency

Quality Dimensions	Frequency
75	30
76	70
77	280
78	500
79	100
80	10
81	10

• What fraction of batteries is expected to survive beyond 1010 days?
• What fraction will survive fewer than 900 days?
• What length of warranty is needed so that no more than 10 percent of the batteries will be expected to fail during the warranty period?

An electronic component in a satellite radio has failure rate of λ = 0.000015 units/hour. Find the mean time to failure (MTTF). What is the probability (assuming an exponential probability distribution) that the component will not have failed after 12,000 hours of operation? Calculate your answer using the appropriate mathematical formul