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1. If the probability that a test for a certain disease gives an accurate result is .92, what is the probability that the test gives an inaccurate result?

   1.   ?    ..08
   2.   ?    .8
   3.   ?    1.08
   4.   ?    None of the answers given; click to see the solution.

2. If A and B are events in a sample space S such that P(A) = .7, P(B) = .2, and P(A B) = .1, find P(A B).

   1.   ?    .8
   2.   ?    .9
   3.   ?    1
   4.   ?    None of the answers given; click to see the solution.

3. In a survey of 250 people concerning how they obtain information about current events, 70 people read a newspaper each day, 130 watch news on television each day, and 30 read a newspaper and watch news on television each day. If a person is selected at random from the group surveyed, what is the (empirical) probability that the person does not either read a newspaper or watch news on television each day?

   1.   ?    .32
   2.   ?    80
   3.   ?    .68
   4.   ?    None of the answers given; click to see the solution.

4. In a survey of 250 people concerning how they obtain information about current events, 70 people read a newspaper each day, 130 watch news on television each day, and 30 read a newspaper and watch news on television each day. If a person is selected at random from the group surveyed, what is the (empirical) probability that the person reads the newspaper but does not watch the news on television each day?

   1.   ?    .16
   2.   ?    40
   3.   ?    .282
   4.   ?    None of the answers given; click to see the solution.

5. In a survey of 250 people concerning how they obtain information about current events, 70 people read a newspaper each day, 130 watch news on television each day, and 30 read a newspaper and watch news on television each day. If a person is selected at random from the group surveyed, what is the (empirical) probability that the person does not read a newspaper each day?

   1.   ?    .72
   2.   ?    180
   3.   ?    .4
   4.   ?    None of the answers given; click to see the solution.

6. This question refers to the data in the table below, obtained from a survey of 500 people regarding three different kinds of toothpaste.
   

   
   
   

   	Prefers Brand A	Prefers Brand B	Prefers Brand C	Totals
   Male	103	70	107	280
   Female	40	95	85	220
   Totals	143	165	192	500

   
   
   
   
   If a person from this survey is selected at random, what is the (empirical) probability that the person prefers Brand B toothpaste?
   1.   ?    .33
   2.   ?    165
   3.   ?    .14
   4.   ?    None of the answers given; click to see the solution.

7. This question refers to the data in the table below, obtained from a survey of 500 people regarding three different kinds of toothpaste.
   

   
   
   

   	Prefers Brand A	Prefers Brand B	Prefers Brand C	Totals
   Male	103	70	107	280
   Female	40	95	85	220
   Totals	143	165	192	500

   
   If a person from this survey is selected at random, what is the (empirical) probability that the person is a male who prefers Brand B or Brand C toothpaste?
   1.   ?    .354
   2.   ?    177
   3.   ?    .56
   4.   ?    None of the answers given; click to see the solution.

8. This question refers to the data in the table below, obtained from a survey of 500 people regarding three different kinds of toothpaste.
   

   
   
   

   	Prefers Brand A	Prefers Brand B	Prefers Brand C	Totals
   Male	103	70	107	280
   Female	40	95	85	220
   Totals	143	165	192	500

   
   
   If a person from this survey is selected at random, what is the (empirical) probability that the person is a female or prefers Brand A toothpaste?
   1.   ?    .646
   2.   ?    .726
   3.   ?    .44
   4.   ?    None of the answers given; click to see the solution.

9. If the probability of event E is 9/13, what are the odds for event E?

   1.   ?    9/4
   2.   ?    4/13
   3.   ?    4/9
   4.   ?    None of the answers given; click to see the solution.

10. If the odds that a certain horse will win a race are 1/5 (which can also be stated as 1:5), what is the probability that the horse will win the race?

    1.   ?    1/6
    2.   ?    1/4
    3.   ?    5/1
    4.   ?    None of the answers given; click to see the solution.

11. A box contains 12 equally sized marbles of which 4 are red and 8 are blue. 5 marbles are selected at random from the box. What is the probability that at least one of the marbles selected is red?

    1.   ?    .93
    2.   ?    .35
    3.   ?    .07
    4.   ?    None of the answers given; click to see the solution.