1.Which pairs of events are independent?

(a)P(A) = 0.30,P(B) = 0.42,P(AB) = 0.15.

(b)P(A) = 0.40,P(B) = 0.90,P(AB) = 0.36.

(c)P(A) = 0.35,P(B) = 0.20,P(AB) = 0.07.

2.The probability that a student has a Visa card (eventV) is .70. The probability that a student has a MasterCard (eventM) is .20. The probability that a student has both cards is .14.

(a)Find the probability that a student has either a Visa card or a MasterCard.(Round your answer to 2 decimal places.)

(b)In this problem, are V and M independent?

3.This contingency table describes 200 business students.

Gender and Major for 200 Business Students

Major

Gender

Accounting (A)

Economics (E)

Statistics (S)

Row Total

Female (F)

40

25

25

90

Male (M)

50

40

20

110

Column Total

90

65

45

200

Is major independent of gender?

Yes

No

4.The probability of being struck by lightning is 0.00045.

Find the odds against being struck by lightning. (Round your answer to the nearest whole number.)

• 1221 to 1
• 221 to 1
• 2221 to 1

5.The probability that an international flight leaving the United States is delayed in departing (eventD) is .36. The probability that an international flight leaving the United States is a transpacific flight (eventP) is .25. The probability that an international flight leaving the U.S. is a transpacific flight and is delayed in departing is .09.

(a)What is the probability that an international flight leaving the United States is delayed in departing given that the flight is a transpacific flight?(Round your answer to 4 decimal places.)

Probability

(b)In this problem, areDandPindependent?

6.Refer to the contingency table shown below.

Smoking by Race for Males Aged 18-24

Smoker

(S)

Nonsmoker

(N)

Row Total

White (W)

289

579

868

Black (B)

37

95

132

Column Total

326

674

1,000

(a)Calculate the probabilities given below:(Round your answers to 4 decimal places.)

i.

P(S)

ii.

P(W)

iii.

P(S|W)

iv.

P(S|B)

v.

P(SandW)

vi.

P(NandB)

(b)Do you see evidence that smoking and race arenotindependent?

multiple choice 1

• Yes
• No

(c)Why might public health officials be interested in this type of data?

multiple choice 2

• Health officials are not interested.
• Health officials might target or design special programs based on race.

7.Health officials can use this as an excuse to explain the lack of initiatives to curb smoking.

Over 1,000 people try to climb Mt. Everest every year. Of those who try to climb Everest, 31 percent succeed. The probability that a climber is at least 60 years old is 0.04. The probability that a climber is at least 60 years old and succeeds in climbing Everest is 0.005.

(a)Find the probability of success, given that a climber is at least 60 years old.

Probability

(b)Is success in climbing Everest independent of age?

YesNo