Elizabeth has just put 4 new spark plugs in her car. For each spark plug, the probability that it will fail in the next 50,000 miles is 1/100 (which is 0.01), and is independent from one spark plug to the next. What is the probability that none of the spark plugs will fail in the next 50,000 miles?
A) (0.01)(0.01)(0.01)(0.01)
B) 1 - (0.01)(0.01)(0.01)(0.01)
C) (0.99)(0.99)(0.99)(0.99)
D) 1 - (0.99)(0.99)(0.99)(0.99)

Question

Quizplus · Accepted Answer

The probability that one spark plug will not fail is 1 - 0.01 = 0.99. Since the failure of each spark plug is independent, the probability that none of the four spark plugs will fail is (0.99)(0.99)(0.99)(0.99).

Elizabeth Has Just Put 4 New Spark Plugs in Her