Statistical Techniques in Business & Economics, Lind/Marchal/Wathen, 13/e
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Chapter 6
Discrete Probability Distributions
40. From recent experience, 5 percent of the computer keyboards produced by an automatic, high-speed
machine are defective. What is the probability that out of six keyboards selected at random, exactly zero
keyboards will be defective?
A) 0.001
B) 0.167
C) 0.735
D) 0.500
Answer: C
41. The probabilities and the number of automobiles lined up at a Lakeside Olds at opening time (7:30
a.m.) for service are:
N
um
b
er Pro
b
a
bili
t
y
1 0.05
2 0.30
3 0.40
4 0.25
On a typical day, how many automobiles should Lakeside Olds expect to be lined up at opening?
A) 10.00
B) 1.00
C) 2.85
D) 1.96
Answer: C
42. On a very hot summer day, 5 percent of the production employees at Midland States Steel are absent
from work. The production employees are randomly selected for a special in-depth study on absenteeism.
What is the probability of randomly selecting 10 production employees on a hot summer day and finding
that none of them are absent?
A) 0.002
B) 0.344
C) 0.599
D) 0.100
Answer: C
44. An insurance agent has appointments with four prospective clients tomorrow. From past experience
the agent knows that the probability of making a sale on any appointment is 1 out of 5. Using the rules of
probability, what is the likelihood that the agent will sell a policy to 3 of the 4 prospective clients?
A) 0.250
B) 0.500
C) 0.410
D) 0.026
Answer: D
