Initial problem
One blood analyzer is operated 120,000 times without failure. It is expected to have 20,000 operations over 5 years with no failures. First, what is the confidence level and reliability if we run this test with no failures? Show work. It appears that both reliability and confidence level can be calculated with only the above information.

The real problem
Then what is the effect on reliability and confidence level if we test more blood analyzers? Surely testing one vs. testing 10 or 30 should change something? What are the equations that use all the above data? What will the new confidence level be if we test 10 or 30 blood analyzers?