Question

400 wrist watches in a box of 10,000 are defective. If 100 watches are selected at random, find the probability that 50 are defective

Answer 1

Explanation:

The probability of selecting a defective watch is 400/10,000 = 2/50.

The probability of selecting 50 defective watches out of 100 selected is given by the binomial distribution:

(100 choose 50) * (2/50)^50 * (1/2)^(100-50) = 0.072.

So the probability that exactly 50 out of 100 selected watches are defective is approximately 0.072.