12. At every one of the Toronto BlueJay's home games, little Johnny is there

with his baseball mit. He wants to catch a ball hit into the stands. Years

of study have suggested that the probability is .0001 that a person sitting

in the type of seats Johnny and his dad sit in will have the opportunity to

catch a ball during any game. Johnny is just turned six years old before the

season started. If he goes to every one of the 81 home games from the start

of the current season until he is 15 years old, what is the probability that

he will have the opportunity to catch a ball.

13. A club has 100 members, 30 of whom are lawyers. Within the club,

25 members are liars and 55 members are neither lawyers nor liars. What

proportion of the lawyers are liars?

14. The following is the probability distribution for an exam where students

have to choose one of two questions. The pass mark is 3 points or more.

5 4 3 2 1

Q1 .1 .1 .1 .2 0.0

Q2 0.0 .2 .1 .1 .1

a) Derive the marginal marks probability distribution.

b) What is the probability that a randomly selected student will pass?

(.6)

c) Given that a randomly selected student got 4 marks, what is the probability that she did question 2?

15. Suppose you are on a game show and you are given the opportunity to

open one of three doors and receive what ever is behind it. You are told

that behind one of the doors is a brand new Rolls Royce automobile and

behind the other two doors are goats. You pick a particular door?say door

number 1?and before the host of the show, who knows what is behind each

door, opens that door he opens one of the other doors?say door number

3?behind which is a goat. He then gives you the opportunity to stay with

door number 1, which you originally chose, or switch your choice to door 2.

Should you switch?

10. We believe that 80% of the population of all Business Statistics students consider statistics to be an exciting subject. Suppose we randomly and independently selected 10 students from this binomial population. a) Find the probability that 4 of the students sampled consider statistics to be an exciting subject. P(x = 4) b) Find # and o for the number of students that consider statistics to be an exciting subject.QUESTION 1 4 points Amna is a student of Zayed university who obtained following scores in the two subjects that she studied. The table below also summarizes the class averages and standard deviations in both classes while there were 20 students in each class. Amna's Scores Class Mean Class St. Deviation Business Calculus 3.80 3.75 0.15 Business Statistics 3.60 3.25 0.60 Her professor suggested her to look at the standardized grades (z-scores) to better judge her performance. What can be suggested by looking at the z-scores? Amna performed best in Business Calculus because it has a higher score. Amna performed best in Business Statistics because it has a higher z-score. Amna performed best in Business Calculus because it has a higher z-score. Amna performed best in Business Statistics because it has a lower z-score.6 of 10 Questions 0:42:24 Question 6 Mark # An insurance company sells automobile liability and collision insurance. Let X denote the percentage of liability policies that will be renewed at the end of their terms and Y the percentage of collision policies that will be renewed at the end of their terms. X and I have the joint cumulative distribution function F(r, v) - n(+y) 0 Sx S 100, 0 Sy SI 2,000,000 Calculate Var(X). 764 833 U 3402 4108 Previous Overview Next