Chapter 5: Quiz

1. A numerical description of the outcome of an experiment is called a
A.descriptive statistic
B.probability function
C.variance
D.random variable
E.none of the above

2. The random variable that can assume only a finite number of values is referred to as a(n)
A.infinite sequence
B.finite sequence
C.discrete random variable
D.discrete probability function
E.none of the above

3. A continuous random variable may assume
A.any value in an interval or collection of intervals
B.only integer calues in an interval or collection of intervals
C.only fractional values in an interval or collection of intervals
D.only the positive integer values in an interval
E.none of the above

The next two questions are based on the information provided below.
The student body of a large university consists of 60% female students.  A random sample of 8 students is selected

4. What is the probability that among the students in the sample exactly two are females?
A.0.0896
B.0.2936
C.0.0413
D.0.0007
E.none of the above

5. What is the probability that among the students in the sample at least 7 are female?
A.0.1064
B.0.0896
C.0.0168
D.0.8936
E.none of the above

6. Four percent of the customers of a mortgage company default on their payments.  A sample of five customers is selected.  What is the probability that exactly two customers in the sample will default on their payments?
A.0.2592
B.0.0142
C.0.9588
D.0.7408
E.0.0000

7. In the textile industry, a manufacturer is interested in the number of blemishes or flaws occurring in each 100 feet of material.  The probability distribution that has the greatest chance of applying to this situation is the
A.normal distribution
B.binomila distribution
C.Poisson distribution
D.uniform distribution
E.none of the above

8. Which of the following is not a characteristic of an experiment where the binomial probability distribution is applicable?
A.the experiment has a sequence of n identical trials
B.exactly two outcomes are possible on each trial
C.the trials are dependent
D.the probabilities of the outcomes do not change from one trial to another
E.all are characteristics of a binomial probability experiment

The next two questions are based on the table provided below.
A local bottling company has determined the number of machine breakdowns per month and their respective probabilities as shown below:

Number of breakdowns	Probability
0	0.12
1	0.38
2	0.25
3	0.18
4	0.07

9. The probability of at least 3 breakdowns in a month is
A.0.5
B.0.10
C.0.30
D.0.90
E.none of the above

10. Thre probability of on breakdowns in a month is
A.0.88
B.0.00
C.0.50
D.0.10
E.none of the above

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