Assignment:
Q: The data named "Time to fail" are the times, in weeks, until a mechanical component failed.
a. Which of the following distributions provide the best fit for the data Normal, Lognormal, and Weibull? Provide your rationale and provide the appropriate parameters to describe the distribution.
b. The warranty is that the life will exceed 125 weeks, what percent of the parts will not meet this life?
c. There have been customer requests to increase the warranty time to 150 weeks which is the same as your main competitor offers. If each of these components cost $1,500 to manufacture what is the additional annual cost to your business to increase the warranty to 150 weeks if your sales are predicted to be 5,000 units per year.
Data are below:
| Time to Failure |
|
|
|
|
| 214.299 |
|
Min Life guarantee 125 |
| 213.272 |
|
|
|
|
| 181.05 |
|
|
|
|
| 179.233 |
|
|
|
|
| 173.306 |
|
|
|
|
| 166.103 |
|
|
|
|
| 205.3 |
|
|
|
|
| 200.153 |
|
|
|
|
| 204.028 |
|
|
|
|
| 216.03 |
|
|
|
|
| 184.948 |
|
|
|
|
| 182.197 |
|
|
|
|
| 208.327 |
|
|
|
|
| 170.332 |
|
|
|
|
| 179.29 |
|
|
|
|
| 197.981 |
|
|
|
|
| 207.208 |
|
|
|
|
| 172.466 |
|
|
|
|
| 198.791 |
|
|
|
|
| 202.163 |
|
|
|
|
| 185.331 |
|
|
|
|
| 194.866 |
|
|
|
|
| 195.39 |
|
|
|
|
| 198.008 |
|
|
|
|
| 200.176 |