An assembly line maufactures engines, where the probability that a given engine is defective is .10. Assuming that the number of engines produced is very large, answer the following
a) If engines are randomly selected one at a time and tested, describe the Probaility Mass Function to use if we want to calculate the probaility that the first working engine will be found on the nth engine tested?
b) What is the probability that the first working enfine will be found on the 2nd engine tested?
c) What is the probility that the 3rd working engine will be found on or before the 5th engine tested?