EXERCISES 11. The events A and B are mutually exclusive. Suppose P(A) = .30 and P(B) = .20. What is the probability of either A or B occurring? What is the probability that neither A nor B will happen? 12. The events X and Y are mutually exclusive. Suppose P(X) = .05 and P(Y) = .02. What is the probability of either X or Y occurring? What is the probability that neither X nor Y will happen? 13. FILE A study of 200 advertising firms revealed their income after taxes: Income after Taxes Number of Firms Under $1 million 102 $1 million to $20 million 61 $20 million or more 37 a. What is the probability an advertising firm selected at random has under $1 million in income after taxes? b. What is the probability an advertising firm selected at random has either an income between $1 million and $20 million, or an income of $20 million or more? What rule of probability was applied? 14. The chair of the board of directors says, "There is a 50% chance this company will earn a profit, a 30% chance it will break even, and a 20% chance it will lose money next quarter." a. Use an addition rule to find the probability the company will not lose money next quarter