718 CHAPTER 11 Probability 33. 3. 1 18 34. 3 if the first die is a 1. 1 6 35. 3 if the first die is a 3. 0 36. an even number if the second die is a 2. 1 2 37. a number greater than 7 if the second die is a 5. 2 3 38. a 7 or 11 if the first die is a 5. 1 3 Problem Solving Taste Test In Exercises 39– 42, use the following results of a coffee taste test given at Lone Star College to first-year and second-year students. Prefers Manhattan’s Finest Coffee Prefers John’s Famous Coffee Total First-year 60 40 100 Second-year 50 75 125 Total 110 115 225 If one of these individuals is randomly selected, determine the probability the individual selected 39. a) prefers John’s Famous Coffee. 23 45 b) prefers John’s Famous Coffee, given that a second-year student is selected. 3 5 40. a) prefers Manhattan’s Finest Coffee. 22 45 b) prefers Manhattan’s Finest Coffee, given that a firstyear student is selected. 3 5 41. a) is a second-year student. 5 9 b) is a second-year student, given that the person prefers John’s Famous Coffee. 15 23 42. a) is a first-year student. 4 9 b) is a first-year student, given that the person prefers Manhattan’s Finest Coffee. 6 11 SunPass In Exercises 43– 46, use the following table, which shows the number of cars and trucks that used the Sunshine Skyway during one particular hour. The number of cars and trucks that used, and did not use, SunPass in that same hour was also recorded. SunPass Cars Trucks Total Used 527 316 843 Did not use 935 683 1618 Total 1462 999 2461 If one of these vehicles is randomly selected, determine the probability (as a decimal number rounded to four decimal places) that the vehicle 43. a) is a car. 0.5941 b) is a car, given that the vehicle used SunPass. 0.6251 44. a) is a truck. 0.4059 b) is a truck, given that the vehicle did not use SunPass. 0.4221 45. a) used SunPass 0.3425 b) used SunPass, given that the vehicle is a car. 0.3605 46. a) did not use SunPass. 0.6575 b) did not use SunPass, given that the vehicle is a truck. 0.6837 Sales Effectiveness In Exercises 47–52, use the following information. Sales representatives at a car dealership were split into two groups. One group used an aggressive approach to sell a customer a new automobile. The other group used a passive approach. The following table summarizes the records for 650 customers. Approach Sale No Sale Total Aggressive 100 250 350 Passive 220 80 300 Total 320 330 650 If one of these customers is randomly selected, determine (as a fraction in lowest terms) the probability 47. that the aggressive approach was used. 7 13 48. of a sale. 32 65 Fizkes/Shutterstock m The Sunshine Skyway Jeff Donald/Shutterstock
RkJQdWJsaXNoZXIy NjM5ODQ=