Probability math homework

Question

A personal computer manufacturer buys 36% of its chips from Japan and the rest from the United States. Of the Japanese chips, 1.6% are defective, and 1.2% of the American chips are defective.

Find the probability that a chip is defective and made in Japan. (Round your answer to four decimal places.)

Answer 1

Since the sample space for the Japanese parts is fully independent of the sample space for the American parts we simply multiply probabilities of .36 chance of being japanese and .016 chance of being defective if Japanese. Chances of a random chip selected from out of the chips being used by the manufacture being Japanese and defective are then

.36 x .016 or .00576 (5.76 parts per thousand or 0.576%)

rounded to 4 decimal places P = .0058