This is just a practice quiz; it does not contain all the possible questions that could
be asked for these sections. Practice quizzes should just be one component of your
studying. As you study you should also use your class notes, study the text sections,
do the suggested homework, study the bonus quizzes, and get help - if needed.
6A questions
1) Which measure of the center of a distribution is most affected by an outlier?
A) mean
B) median
C) mode
D) variation
2) Which of the following is true in a right skewed distribution?
A) mean < median < mode
B) mode < median < mean
C) mean = median = mode
D) median = mean < mode
3) A data value that is much higher or lower than almost all other values is called a (an)
A) extreme B) outlier
C) max/min D) unusual
4) The _______________ describes how widely data values are spread out about the
center of the distribution.
A) mean
B) median
C) outlier
D) variation
5) A data set that has two peaks is called:
A) symmetric
B) bimodal
C) skewed
D) unimodal
6) Find the mean of the following set of data: 3.5, 4.8, 4.5, 3.6, 4.9
7) Find the median of the following set of data: 3.5, 4.8, 4.5, 3.6, 4.9
8) Find the median of the following set of data: 3.5, 4.8, 4.5, 3.6, 4.9, 3.5, 4.1, 3.5
9) Find the mode of the following set of data: 3.5, 4.8, 4.5, 3.6, 4.9, 3.5, 4.1, 3.5
6B questions
1) Which of the following is not a measure of the variation of a data set.
A) mean
B) range
C) standard deviation
2) In a typical data set, what fraction of the data values lie at or below the upper quartile?
A) 1 (all the data)
B) 1/4
C) 1/2
D) 3/4
3) For this data set: 52, 48, 50, 54, 58, 56, 60
a) Calculate the range.
b) Calculate the standard deviation (to the nearest hundredth).
c) Approximate the standard deviation using the range rule of thumb.
d) Calculate the five-number summary.
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4) Given a data set with mean 150 and standard deviation 10, estimate the high and low
values for this data set.
5) The box plot shown represents the grades of 200 students. Use the box plot to answer
the following questions.
a. Approximately how many students
scored below 80?
b. Approximately how many students
scored below 90?
c. What score is the lower quartile?
d. What is the median?
e. What was the lowest score?
Answers 6A: 1) A 2) B 3) B 4) D 5) B 6) 4.26 7) 4.5 8) 3.85 9) 3.5
Answers 6B: 1) A 2) D 3a) 12 3b) 4.32 3c) 3 3d) low = 48; lower quartile = 50;
median = 54; upper quartile = 58; high = 60 4) approx high ≈ 170, approx low ≈ 130
5a) 100 5b) 150 5c) 60 5d) 80 5e) 40
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