WorksheetsDescriptive statistics - Unit quiz
Total questions: 20
Worksheet time: 16mins
When a set of data has suspect outliers, which of the following are preferred measures of central tendency and of variability?
mean and standard deviation
mean and variance
mean and range
median and range
median and interquartile range
If the standard deviation of a set of observations is 0, you can conclude
that there is no relationship between the observations.
that the average value is 0.
that all observations are the same value.
that a mistake in arithmetic has been made.
none of the above.
Data on the number of text messages sent one weekend by junior and senior high school students in a large high school is summarized as follows:
An AP Statistics student checking the calculations finds that the message counts for all the students were underreported by 5. When the numbers are corrected, what are the corrected IQR and standard deviation?
IQR = 71 and standard deviation = 41.2
IQR = 71 and standard deviation = 46.2
IQR = 76 and standard deviation = 41.2
IQR = 76 and standard deviation = 46.2
IQR = 146 and standard deviation = 41.2
Suppose the starting salaries of a graduating class are as follows:
What is the mean starting salary?
$30,000
$30,533
$32,500
$32,533
$35,000
For which of the following variables would it be most appropriate to construct a histogram?
Television brand
Insect species
Gender
Eye color
Phone call length
Given that the median of a set is 350 and the interquartile range is 50, which of the following statements is true?
Fifty percent of the data are less than or equal to 350.
Fifty percent of the data are between 325 and 375.
Seventy-five percent of the data are less than or equal to 375.
The mean is between 325 and 375.
All of the above statements are true.
A random sample of scores at a bowling alley one day gives the following summary statistics:
n = 26,
x = 132.34, s = 10.18, min = 113, Q1 = 126,
med = 134.5, Q3 = 139, and max = 160
How many outliers are there?
0
1
2
At least 1
At least 2
On a large campus, 500 students were surveyed about their belief in an afterlife. The following table shows their responses categorized by class.
Of the following graphical displays, which is the most appropriate to compare the proportions of students in each class who believe in an afterlife?
Back-to-back stem plot
Parallel boxplots
Scatterplot
Segmented bar chart
Cumulative frequency plot
Counts of the numbers of spam messages received by a company’s executives during one week are summarized below.
How many outliers are there?
0
1
2
3
4
In which of the following histograms is the mean greater than the median?
The prices at which a particular AP Statistics review book are sold at 92 online sites are summarized in the table below.
Which of the following best describes the distribution of prices?
Roughly normal
Skewed left
Skewed right
Skewed both left and right
Bimodal
For the histogram pictured below, what proportion of the terms are less than 3.5?
Write your answer as a decimal.
(a)
Twenty-five randomly selected students were asked the number of movies they watched the previous week. The results are as follows:
Find the sample mean to 2 decimal places.
(a)
Twenty-five randomly selected students were asked the number of movies they watched the previous week. The results are as follows:
Find the approximate sample standard deviation, s. to 2 decimal places.
(a)
X = the number of days per week that 100 clients use a particular exercise facility.
The 80th percentile is _____
5
80
3
4
The number that is 1.5 standard deviations BELOW the mean is approximately _____
0.7
4.8
-2.8
Cannot be determined
The list below shows the most recent test scores for students in Mr. Garcia’s study group.
78, 90, 94, 72, 80, 68, 72, 88, 94, 98, 86, 96
Which box-and-whisker plot correctly represents the data in the list?
