11.7 Problems

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1. How are series and parallel reliability different?

ans. Series reliability means that a failure of any unit will cause the entire group to fail. Parallel reliability means that there is some redundancy.

2. A set of 4 production machines are running in parallel. The first two machines have a MTBF of 100 hours and a MTTR of 3 hours. The second two machines have a MTBF of 150 hours and a MTTR of 15 hours. What is the total MTTF for the system?

3. Write a program that will accept test data to determine the Exponential Failure Equation coefficient. This should then be used to calculate the MTTF.

4. Write a program that will accept MTTF for multiple components in series, or parallel, and then calculate the combined MTTF for the system.