Statistics Exam #2 Study Guide Sullivan Survey: Speeding Tickets. The following
ID: 3055885 • Letter: S
Question
Statistics Exam #2 Study Guide Sullivan Survey: Speeding Tickets. The following data represent the number of speeding tickets issued to individuals in the past year and the gender of the indiv following probabilities based on the result of the 1. iduals. Determine the Total 115 82 197 14 Male Total 97 71 168 21 a) Determine the probability a randomly selected driver is female. b) Determine the probability a randomly selected driver has been issued 3 tickets in the past year e) Determine the probability a randomly selected driver is male and has been issued 3 tickets in the past year Determine the probability a randomly selected driver is male or has been issued 3 tickets in the past year d) e) What is the probability that a randomly selected individual was issued 2 tickets last year, given 1) What is the probability that a randomly selected individual is female, given the individual was g) the individual is male? issued 3tickes in the past year? What is the probability that a randomly selected individual was issued 0 tickets last year? Life Expectancy. The probability that a randomly selected 40-year-female will live to be 41 years old is 0.99855 according to the National Vital Statistics Report, Vol. 56. No 9 2. What is the probability that three randomly selected 40-year-old females will live to be 41 years old? What is the probability that at least one of four randomly selected 40-year-old female will not live to be 41 years old? a) b) Effectiveness of Vaccine. A vaccine has a 90% probability of being effective in preventing a certain disease. The probability of getting the disease if a person is not vaccinated is 50%. In a certain geographical region, 25% of the people get vaccinated. If a person is selected at random find the probability that he or she will contract the disease. [Hint: This is a total probability problem 3, Planting Tulips. A bag of 35 tulip bulbs purchased from a nursery contains 14 red tulip bulbs, 9 yellow tulip bulbs, and 12 purple tulip bulbs. Two tulip bulbs are drawn without replacements 4. a) What is the probability that two randomly selected tulip bulbs are both red? b) What is the probability that first bulb selected is yellow and the second is red? c) What is the probability that the first bulb selected is red and the second is purple? d) What is the probability that at least one tulip is purple? 5. Children. A family has five children. If this family has exactly two boys, how many different birth and gender orders are possible?Explanation / Answer
Answer to the question is as follows:
1. P(female) = 115/197 = .5838
2. P(issued 3 tickets in past year) = 4/197 = 0.0203
3. P(male ,issued 3 tickets in past year) = 3/197 = 0.0152
4. P(male or has been issued 3 tickets in past year) = (82+4-3)/197 = .4213. We used the formula here: P(A U B) = P(A)+P(B)-P(A & B)
5. P(given individual was issued 3 tickets, is female) = 1/4= .25
6. P(issued 0 tickets) = (168/197) = 0.8528