Question

1- In an experiment, college students were given either four quarters or a $1 bill and they could either keep the money or spend it on gum. The results are summarized in the table. Complete parts (a) through (c) below. Students Given Four Quarters Students Given a $1 Bill Purchased Gum 27 12 kept the Money 16 28 a. Find the probability of randomly selecting a student who spent the money, given that the student was given four quarters The probability is (Round to three decimal places as needed.) b. Find the probability of randomly selecting a student who kept the money. given that the student was given four quarters. The probability is (Round to three decimal places as needed.) c. What do the preceding results suggest? O A. A student given four quarters is more likely to have kept the money. OB. A student given four quarters is more likely to have spent the money than a student given a $1 bill OC. A student given four quarters is more likely to have spent the money OD. A student given four quarters is more likely to have kept the money than a student given a $1 bill. 2- Refer to the sample data for pre-employment drug screening shown below. If one of the subjects is randomly selected, what is the probability that the test result is a false positive? Who would suffer from a false positive result? Why? Pre-Employment Drug Screening Results Positive test result Negative test result Drug Use Is Indicated Drug Use Is Not Indicated Subject Uses Drugs 45 10 Subject Is Not a Drug User 15 31 The probability of a false positive test result is (Round to three decimal places as needed.) Who would suffer from a false positive result? Why? O A. The employer would suffer because the person tested would be suspected of using drugs when in reality he or she does not use drugs. OB. The employer would suffer because the person tested would not be suspected of using drugs when in reality he or she does use drugs. OC. The person tested would suffer because he or she would not be suspected of using drugs when in reality he or she does use drugs. OD. The person tested would suffer because he or she would be suspected of using drugs when in reality he or she does not use drugs. 3- When a man observed a sobriely checkpoint conducted by a police department, he saw 681 drivers were screened and 5 were arrested for driving while intoxicated. Based on those results, we can estimate that P(W) = 0.00734, where W denotes the event of screening a driver and getting someone who is intoxicated. What does P(W) denote, and what is its value? What does P(W) represent? A. P(W) denotes the probability of screening a driver and finding that he or she is not intoxicated. B. P(W) denotes the probability of a driver passing through the sobriety checkpoint. C. P(W) denotes the probability of screening a driver and finding that he or she is intoxicated. OD P(W) denotes the probability of driver being intoxicated. P(W) - (Round to five decimal places as needed.)

Answer 1

Purchased Cum student kept Total noney • Student given 4 quarter 27 16 43 Student Given & biu Yo Total 39 44 83

1 a) given student will P ( who spent money four quarters P ( purcha peschased gun given student given quarters in form P (purchased gum n student given a quarks) PL shodlent given for quarters) 27 83 43 83 Il 27 43 lo 628 ① l l who kept money given student givent quarter) PC who kept money n stodent goven 4 quark) P (student given 4 quarter) 16 0.312 43 33 83 Il 16 43

© 4 quarter) pl who spent monly given is greater so a stodent giver four quarta have spent money option correct ند more likely to goan So. of Positive Test Subject Use Doug 45 Teue Posilive Subject Not a Doug User 46 Negatie Test Total ip 55 false Negative 3 Tove Alegetve YI 100 15 false Positive Total 6o Pl false P positive LI Number of false positive Total sample il 15 101 0.14851485 I 10:149

9 would suffer be The person tested becawe he a she would suspected using drug drug while she doen not we drug D © Correct. option of 07 reality he li co a P(W) denote the Probability ol screeninga driven and finding that he abe is not intoxcated. Option Corred P(w) = 1 - Plo) 0.00734 = 0.99266 is