8.
A statistics instructor wants to measure the effectiveness of his teaching skills in a class of
102 students (
N
= 102). He selects students by waiting at the door to the classroom prior to
his lecture and pulling aside every third student to give him or her a questionnaire.
a.
Is this sample design an example of random sampling? Explain.
Assuming that all students attend his class that day, how many students will the instructor
select to complete his questionnaire?
9.
Suppose you were going to conduct a survey of visitors to your campus. You want the survey
to be as representative as possible.
a.
How would you select the people to survey?
b.
Why would that be your best method?

WEEK TWO PRACTICE WORKSHEET
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10.
In a school band, 9 kids play string instruments, 10 kids play woodwind instruments, 7 kids
play brass instruments, and 4 kids play percussion instruments.
a.
What is the probability that you randomly select a kid who plays a string or percussion
instrument?
b.
What is the probability that you randomly select a kid who does not play a brass
instrument?

WEEK TWO PRACTICE WORKSHEET
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References:
Aron, A., Coups, E. J., & Aron, E. N. (2013). Statistics for Psychology (6th ed.). Retrieved from
The University of Phoenix eBook Collection.