CHAPTER 5: Normal, Binomial, Poisson, and Exponential Distributions

 

MULTIPLE CHOICE

1. 
   The higher the value of the density function f(x),
   

ANS:  B                    PTS:   1

2. 
   Tossing a coin is an example of a (n)
   

ANS:  A                    PTS:   1

3. 
   We assume that the outcomes of successive trials in a binomial experiment are:
   

ANS:  A                    PTS:   1

4. 
   One reason for standardizing random variables is to measure variables with:
   

ANS:  B                    PTS:   1

5. 
   If the value of the standard normal random variable Z is positive, then the original score is where in relationship to the mean?
   

ANS:  C                    PTS:   1

6. 
   The normal distribution is:
   

ANS:  D                    PTS:   1

7. 
   The standard deviation  of a probability distribution is a:
   

ANS:  A                    PTS:   1

8. 
   The mean  of a probability distribution is a:
   

ANS:  B                    PTS:   1

9. 
   If we plot a continuous probability distribution f(x), the total probability under the curve is
   

ANS:  C                    PTS:   1

10. 
    A continuous probability distribution is characterized by:
    

ANS:  D                    PTS:   1

11. 
    Which of the following equations shows the process of standardizing?
    

ANS:  B                    PTS:   1

12. 
    A Poisson distribution is:
    

ANS:  C                    PTS:   1

13. 
    The standard normal distribution has a mean and a standard deviation respectively equal to
    

ANS:  D                    PTS:   1

14. 
    Sampling done without replacement means that
    

ANS:  C                    PTS:   1

15. 
    The Poisson random variable is a:
    

ANS:  A                    PTS:   1

16. 
    Which probability distribution applies to the number of events occurring within a specified period of time or space
    

ANS:  B                    PTS:   1

17. 
    Which of the following might not be appropriately modeled with a normal distribution?
    

ANS:  D                    PTS:   1

18. 
    The variance of a binomial distribution for which n = 100 and p = 0.20 is:
    

ANS:  D                    PTS:   1

19. 
    The binomial probability distribution is used with
    

ANS:  A                    PTS:   1

20. 
    Given that Z is a standard normal random variable, P(-1.0Z1.5) is
    

ANS:  A                    PTS:   1

21. 
    Given that Z is a standard normal variable, the value z for which P(Z  z) = 0.2580 is
    

ANS:  C                    PTS:   1

22. 
    If the random variable X is exponentially distributed with parameter = 3, then P(X  2) , up to 4 decimal places , is
    

ANS:  D                    PTS:   1

23. 
    If the random variable X is exponentially distributed with parameter = 1.5, then P(2X  4), up to 4 decimal places, is
    

ANS:  B                    PTS:   1

24. 
    If X is a normal random variable with a standard deviation of 10, then 3X has a standard deviation equal to
    

ANS:  C                    PTS:   1

25. 
    Given that the random variable X is normally distributed with a mean of 80 and a standard deviation of 10, P(85 X 90) is
    

ANS:  D                    PTS:   1

26. 
    The Poisson and Exponential distributions are commonly used in which of the following applications
    

ANS:  A                    PTS:   1

27. 
    Which of the following distributions is appropriate to measure the length of time between arrivals at a grocery checkout counter?
    

ANS:  C                    PTS:   1

28. 
    If the mean of an exponential distribution is 2, then the value of the parameter  is
    

ANS:  D                    PTS:   1