In: Statistics and Probability
Suppose that 10% of the engines manufactured on a certain assembly lineare defective. If engines are randomly selected one at a time and tested,
(a) (4 points) Calculate the probability that two good engines will be testedbefore a defective engine is found.
(b) (4 points) Calculate the probability that at least three good engineswill be tested before a defective engine is found.
(c) (2 points) Calculate the expected value of the number of good enginestested before a defective engine is found.
a) probability that two good engines will be tested before a defective engine is found =0.9*0.9*0.1=0.081
b) probability that at least three good engines will be tested before a defective engine is found =P(all three are good)
=0.9*0.9*0.9=0.729
c)
expected value of the number of good enginestested before a defective engine is found =1/p=1/0.1=10