Download Practice SHORT ANSWER. Write the word or phrase that best

Practice
SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.
Provide an appropriate response.
1) In interpreting a boxplot of a data set we note that the median is to the left of the center of the box and the right
line is longer than the left line. We can conclude that the shape of the distribution is
2) What are the measures of dispersion?
3) The population mean is symbolized by
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
4) A statistic is said to be biased if it
A) Systematically underestimates or overestimates a parameter
B) Has exactly the same value as the parameter
C) Leads to an erroneous conclusion about the sample
D) Is determined from a trimmed sample
SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.
5) The monthly telephone usage (in minutes) of 30 adults is listed below. Find the interquartile range for the
telephone usage of the 30 adults.
154 156 165 165 170 171 172 180 184 185
189 189 190 192 195 198 198 200 200 200
205 205 211 215 220 220 225 238 255 265
6) For the following data, approximate the mean number of unused vacation days at the end of the year.
Days Frequency
1-2
27
3-4
13
5-6
17
7-8
4
9-10
24
7) The normal monthly precipitation (in inches) for August is listed for 20 different U.S. cities. Find any outliers
and provide an explanation for them.
0.4
2.2
3.5
3.9
1.0
2.4
3.6
4.1
1.5
2.7
3.6
4.2
1.6
3.4
3.7
4.2
2.0
3.4
3.7
7.0
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8) The grades are given for a student for a particular term. Find the grade point average. The point values of grades
are given below.
A : 4, B : 3,
C : 2,
D : 1, F : 0
Grade
Credit Hours
A
B
A
B
B
3
2
2
3
3
9) The high temperatures (in degrees Celsius) each day over a three week period were as follows: 17, 18, 20, 22, 21,
19, 16, 15, 18, 20, 21, 21, 22, 21, 19, 20, 19, 17, 16, 16, 17. Compute the mean, median, and mode.
10) The following is a sample of 19 November utility bills (in dollars) from a neighborhood.What is the largest bill
in the sample that would not be considered an outlier?
52, 62, 66, 68, 72, 74, 76, 76, 76, 78, 78, 82, 84, 84, 86, 88, 92, 96, 110
11) Describe the shape of the histogram. The data set: round-trip commuting times (in minutes) of 20 randomly
selected employees
135 120 115 132 136 124 119 145 98 110
125 120 115 130 140 105 116 121 125 108
12) Each year advertisers spend billions of dollars purchasing commercial time on network sports television. In the
first 6 months of 1988, advertisers spent $1.1 billion. A recent article listed the top 10 leading spenders (in
millions of dollars):
Company A
Company B
Company C
Company D
Company E
$70
61.8
55.6
55.3
31.7
Company F $27.2
Company G 25.8
Company H 21.7
Company I
23.3
Company J
20.6
Calculate the median.
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13) A group of 79 students were asked how far they commute to work from home each time they go to work from
home. The results are given below. Determine the first quartile.
Miles
traveled
1
2
3
4
5
6
7
8
9
10
Frequency
1
2
12
18
7
10
10
11
5
3
14) For the following data set, approximate the sample standard deviation of distances from work (in miles).
Distance(miles) Frequency
8-11
15
12-15
21
16-19
36
20-23
39
24-27
23
15) A student scores 74 on a geography test and 282 on a mathematics test. The geography test has a mean of 80 and
a standard deviation of 5. The mathematics test has a mean of 300 and a standard deviation of 12. If the data for
both tests are normally distributed, on which test did the student score better relative to the other students in
each class?
16) At a tennis tournament a statistician keeps track of every serve. The statistician reported that the mean serve
speed of a particular player was 100 miles per hour (mph) and the standard deviation of the serve speeds was
13 mph. If nothing is known about the shape of the distribution, give an interval that will contain the speeds of
at least three-fourths of the player's serves.
17) The percentage of measurements that are below the 88th percentile is
18) The amount of television viewed by today's youth is of primary concern to Parents Against Watching Television
(PAWT). 300 parents of elementary school-aged children were asked to estimate the number of hours per week
that their child watched television. The mean and the standard deviation for their responses were 18 and 5,
respectively. PAWT constructed a stem-and-leaf display for the data that showed that the distribution of times
was a bell-shaped distribution. Give an interval around the mean where you believe most (approximately 95%)
of the television viewing times fell in the distribution.
Compute the range for the set of data.
19) 8, 9, 10, 11, 12
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