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ST 15. A region is prone to flooding once every 20 years, The probability of flooding in any one year is . What is the probability of flooding for three consecutive years? 16. One card is randomly selected from a deck of 52 cards Find the probability of selecting a black card or a picture card. 17. A group of students consists of 10 male freshmen, 15 female freshmen. 20 male sophomores and 5 female sophomores If one person is randomly selected from the group, find the probability of selecting a freshman or a female. 18. A box contains five red balls, six green balls, and nine yellow balls Suppose you select one ball at random from the box and do not replace it. Then you randomly select a second ball. Find the probability that both balls selected are red. 19. A quiz consisting of four multiple-choice questions has four available options (a. b. c. or d) for each question. If a person guesses at every question, what is the probability of answering all questions correctly? 20. A group is comprised of 20 men and 15 women. If one person is randomly selected from the group. find the odds against the person being a man. 21. The odds against a candidate winning an election are given at 1 to 4. a. What are the odds in favor of the candidate winning? b. What is the probability that the candidate will win the election? A class is collecting data on eye color and gender. They organize the data they collected into the table shown. Numbers in the table represent the number of students from the class that belong to each of the categories. Use the data to solve Exercises 22-26. Express probabilities as simplified fractions. Brown Blue Green Male 22 18 10 Female IS 20 12 Find the probability that a randomly selected student from this class 22. does not have brown cyes. 23. has brown eyes or blue eyes. 24. is female or has green eyes. 25. is male. given the student has blue eyes. 26. If two people are randomly selected, in succession, from the students in this class. find the probability that they both have green eyes. 27. An architect is considering bidding for the design of a new theater. The cost of drawing plans and submitting a model is $15.000. The probability of being awarded the bid is 0.2. and anticipated profits are $80.000, resulting in a possible gain of this amount minus the $15.000 cost for plans and models. What is the expected value if the architect decides to bid for the design? Describe what this value means. 28. A game is played by selecting one bill at random from a bag that contains ten $1 bills. five $2 bills, three $5 bills, one $10 bill. and one $100 bill. The player gets to keep the selected bill. There is a $20 charge to play the game. What is the expected value? What does this value mean
