A manufacturing machine has a 3% defect rate. If 5 items are chosen at random, what is the probability that at least one will have a defect?

Answer 1

Hi Kaitlyn:

Prob of a defective item is 0.03 => Prob(non-defective) = 1 - 0.03 = 0.97

Now Prob(at least one defect) = 1 - Prob(0 defects)

= 1 - 5C0 x 0.03^0 x 0.97^5

= 1 - 1 x 1 x 0.85

= 0.15 or 15%