Final exam
Exhibit 6-2The travel time for a college student traveling between her home and her college is uniformly distributed between 40 and 90 minutes. Refer to Exhibit 6-2. The probability that she will finish her trip in 80 minutes or less is _____.
.8
Exhibit 5-1The following represents the probability distribution for the daily demand of microcomputers at a local store. Demand Probability 0 .1 1 .2 2 .3 3 .2 4 .2 Refer to Exhibit 5-1. The expected daily demand is _____.
2.2
Exhibit 5-11 The random variable x is the number of occurrences of an event over an interval of 10 minutes. It can be assumed the probability of an occurrence is the same in any two time periods of an equal length. It is known that the mean number of occurrences in 10 minutes is 5.3. Refer to Exhibit 5-11. The appropriate probability distribution for the random variable is _____.
Discrete
In hypothesis testing, the critical value is _____.
a number that establishes the boundary of the rejection region
Categorical data can be graphically represented by using a(n) _____.
bar chart
In an application for a credit card, potential customers are asked for their social security numbers. A social security number is an example of a _____.
categorical variable
The confidence associated with an interval estimate is called the _____.
confidence level
Which two scales of measurement can be either numeric or nonnumeric?
nominal and ordinal
An important application of the chi-square distribution is _____.
testing for equality of three or more population proportions testing for the independence of two variables testing for goodness of fit All of the answers are correct.
Exhibit 10-13 In order to determine whether or not there is a significant difference between the hourly wages of two companies, the following data have been accumulated. Company 1Company 2 n1 = 80n2 = 60 1 = $10.802 = $10.00 σ1= $2.00σ2= $1.50 Refer to Exhibit 10-13. Thep-value is _____.
.007
Which of the following is not a measure of dispersion?
50th percentile
Exhibit 7-5Random samples of size 17 are taken from a population that has 200 elements, a mean of 36, and a standard deviation of 8. Refer to Exhibit 7-5. The mean and the standard deviation of the sampling distribution of the sample means are _____.
36 and 1.86
Exhibit 12-5The table below gives beverage preferences for random samples of teens and adults. Beverage Teens Adults Total Coffee 50 200 250 Tea 100 150 250 Soft drink 200 200 400 Other 50 50 100 400 600 1,000 We are asked to test for independence between age (i.e., adult and teen) and drink preferences. Refer to Exhibit 12-5. With a .05 level of significance, the critical value for the test is _____.
7.815
Each customer entering a department store will either buy or not buy some merchandise. An experiment consists of following three customers and determining whether or not they purchase any merchandise. The number of sample points in this experiment is _____.
8
Whenever the population has a normal probability distribution, the sampling distribution of is a normal probability distribution for _____.
Any sample size
The variance of a sample or a population cannot be _____.
Negative
The error of rejecting a true null hypothesis is _____.
Type I error
Which of the following is NOT an example of a firm that sells or leases business database services to clients?
U.S. Census Bureau
Initial estimates of the probabilities of events are known as _____.
prior probabilities
A graphical method that can be used to show both the rank order and shape of a data set simultaneously is a _____.
stem-and-leaf display