A System Is Composed of Two Parts Which Must Both

Multiple Choice

A system is composed of two parts which must both operate in order for the system to perform as intended.The parts have reliabilities of .6 and .5.There is an identical backup for each part.The backup system is connected to the main system by a switch which has a reliability of .9.The probability that the overall system will operate is closest to:

A) .30
B) .40
C) .50
D) .60
E) .70