At a certain pizza parlor, 65% of the customers order a pizza containing onions, 61% Of the customers order a pizza containing sausage, and 72% order a pizza containing onions or sausage (or both). Find the probability that a customer chosen at random will order a pizza containing both onions and sausage. Write your answer as a decimal (not as a percentage). (If necessary, consult a list of formulas.) ?

Jack has just been given a ten-question multiple choice quiz in history class. Each question has five answers, of which only one is correct. Since Jack has not attended class recently, he does not know any of the answers. Assuming Jack guesses randomly on all ten questions, find the probability that he will answer six or more of the questions correctly and avoid an F.