500 câu trắc nghiệm Kinh tế lượng – 3C
11) In one town, 37% of all voters are Democrats. If two voters are randomly selected for a survey, find the probability that they are both Democrats.
○ 0.133
● 0.137
○ 0.740
○ 0.370
12) A sample of 4 different calculators is randomly selected from a group containing 36 that are defective and 29 that have no defects. What is the probability that all four of the calculators selected are defective?
○ 0.0941
○ 0.4211
● 0.0870
○ 2.4801
Provide a written description of the complement of the given event.
13) When 10 adults are tested for high blood pressure, at least one of the results are positive.
● None of the adults have high blood pressure.
○ Nine of the adults have high blood pressure.
○ All of the adults have high blood pressure.
Find the indicated probability.
14) In a batch of 8,000 clock radios 2% are defective. A sample of 12 clock radios is randomly selected without replacement from the 8,000 and tested. The entire batch will be rejected if at least one of those tested is defective. What is the probability that the entire batch will be rejected?
○ 0.785
○ 0.0833
○ 0.0200
● 0.215
15) The table below shows the soft drinks preferences of people in three age groups.
| cola | root beer | lemon-lime | |
| under 21 years of age | 40 | 25 | 20 |
| between 21 and 40 | 35 | 20 | 30 |
| over 40 years of age | 20 | 30 | 35 |
If one of the 255 subjects is randomly selected, find the probability that the person is over 40 years of age given that they drink root beer.
○ 5/17
○ 6/17
● 2/5
○ None of the above is correct.
16) The following table contains data from a study of two airlines which fly to Small Town, USA.
| Number of flights which were on time | Number of flights which were late | |
| Podunk Airlines | 33 | 6 |
| Upstate Airlines | 43 | 5 |
If one of the 87 flights is randomly selected, find the probability that the flight selected arrived on time given that it was an Upstate Airlines flight.
○ 43/87
○ 11/76
● 43/48
○ None of the above is correct.
Solve the problem.
17) A firm uses trend projection and seasonal factors to simulate sales for a given time period. It assigns “0” if sales fall, “1” if sales are steady, “2” if sales rise moderately, and “3” if sales rise a lot. The simulator generates the following output.
0 1 1 2 0 0 1 1 0 3 2 1 0 1 0 2 1 2 3 1 2 0 2 0 3 1 0 2 1 0 1
Estimate the probability that sales will rise moderately.
○ 0.312
○ 0.233
● 0.226
○ 0.258
Evaluate the expression.
18) 10P3
○ 120
○ 7
○ 27
● 720
Solve the problem.
19) 8 basketball players are to be selected to play in a special game. The players will be selected from a list of 27 players. If the players are selected randomly, what is the probability that the 8 tallest players will be selected?
○ 1/213,127,200
○ 1/40,320
● 1/2,220,075
○ 8/27
20) A pollster wants to minimize the effect the order of the questions has on a person’s response to a survey. How many different surveys are required to cover all possible arrangements if there are 6 questions on the survey?
○ 120
● 720
○ 6
○ 36