Suppose that half of the parent flies are known to be mutants. Of 20 offspring flies inspected, none have purple eyes. What is the conditional probability that the parents are mutants? If parents are discarded if all 20 offspring have normal eyes, what fraction of mutant parents will be discarded?
A lab is screening to find mutant flies. 10% of the offspring of mutant flies have purple eyes, while none of the offspring of wild type flies have purple eyes. Suppose that purple-eyed flies are just as easy to catch as ordinary flies.