Consider a space rocket propulsion system in which the main

Consider a space rocket propulsion system in which the main engine

has a backup unit. These engines are designed to operate independently in

that the success or failure of one has no effect on the other. The propulsion

system is operable if one or the other of these two engines is operable. Assume

that each engine functions correctly with a probability of 0.90. Find the

probability that the propulsion system is operable.

Solution

Note that

P(at least one operable) = 1 - P(both not operable)

= 1 - (1-0.9)*(1-0.9)

= 0.99 [ANSWER]