Suppose two dice, one blue and one red, are rolled and the outcomes of each are recorded. We define the following two events:
A: sum of the roll is 7
B. the result of the blue die is a number greater than 4
Are the two events, A and B, independent events?
A) No B) Yes
Q. 2Classify the events as dependent or independent: Events A and B where and
A) dependent B) independent
Q. 3During one recent year, U.S. consumers redeemed 6.31 billion manufacturers' coupons and saved themselves 2.56 billion. Calculate and interpret the mean savings per coupon.
A) Half of all coupons were worth more than 0.41 in savings.
B) Half of all coupons were worth more than 246.5 cents in savings.
C) The average savings was 0.41 per coupon.
D) The average savings was 246.5 cents per coupon.
Q. 4If P(A ) = .55, P(B ) = .4, P(A B ) = .22, and A and B are independent events, find P(B ).
A) .88 B) .55 C) .22 D) .4
Q. 5We believe that 81 of the population of all Business Statistics students consider statistics to be an exciting subject. Suppose we randomly and independently selected 39 students from the population.
How many of the sampled students do we expect to consider statistics to be an exciting subject?
A) 39 B) 31.59 C) 33.82 D) 32.16
Q. 6According to a published study, 1 in every 10 men has been involved in a minor traffic accident. Suppose we have randomly and independently sampled twenty-five men and asked each whether he has been involved in a minor traffic accident.
How many of the 25 men do we expect to have never been involved in a minor traffic accident? Round to the nearest whole number.
A) 25 B) 3 C) 10 D) 22
Q. 7A recent survey found that 70 of all adults over 50 wear glasses for driving. In a random sample of 40 adults over 50, what is the mean and standard deviation of the number who wear glasses? Round to the nearest hundredth when necessary.
A) mean: 12; standard deviation: 5.29 B) mean: 28; standard deviation: 2.9
C) mean: 12; standard deviation: 2.9 D) mean: 28; standard deviation: 5.29
Q. 8If P(A B ) = 0 and P(A ) 0, then which statement is false?
A) Events A and B are dependent.
B) Events A and B are mutually exclusive.
C) Events A and B have no sample points in common.
D) Events A and B are independent.
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