-- Well, that was pretty obvious.
I think the '3' on the end is the hardest part.
I'm rather surprised by the result. Maybe it's wrong. Think it through.
The lifetime of a component computer is exponentially distributed with mean 1 year. Management hopes to increase the reliability by replacing the component with a new one if it has not failed after 2 years.
Compute the mean lifetime of the components used in the computers with the replacement policy.