Abicycle manufacturer is studying the reliability of one of its models. the study finds that the probability of a brake defect is 4 percent and the probability of both a brake defect and a chain defect is 1 percent. if the probability of a defect with the brakes or the chain is 6 percent, what is the probability of a chain defect

Let the probability of a brake defect be P(B), the probability of a chain defect be P(C) then the probability of a brake and a chain defect is P(B ∩ C) and the probability of a brake or a chain defect P(B ∪ C).

Given that P(B) = 4%, P(C) = ?, P(B ∩ C) = 1%, P(B ∪ C) = 6%.

P(B ∪ C) = P(B) + P(C) - P(B ∩ C)
Thus, P(C) = P(B ∪ C) + P(B ∩ C) - P(B) = 6% + 1% - 4% = 3%