An overthecounter pregnancy test claims to be 99 accurate Ac

An over-the-counter pregnancy test claims to be 99% accurate. Actually, what the insert says is that if the test is performed properly, it is 99% sure to detect a pregnancy.

(a) What is the probability of a false negative?

(b) Let us assume that the probability is 98% that the test result is negative for a woman who is not pregnant. If the woman estimates that her chances of being pregnant are about 40% and the test result is positive, what is the probability that she is actually pregnant?

Solution