Question: A Helicopter is equipped with three engines that operate independently. The probability of an engine failure is 0.01. What is the probability of successful fight if only one engine is needed for the successful operation of the aircraft?

Solution:

Since the flight is unsuccessful only when all the three engines fail, then the

probability of unsuccessful flight is:
.01 x .01 x.01 = .000001.

The probability of successful flight = 1 – .000001 = .999999.