94 Numerical Descriptive Measures
TABLE 3-5
The rate of return of a Fortune 500 company over the past 15 years are: 3.17%, 4.43%, 5.93%, 5.43%, 7.29%, 8.21%, 6.23%, 5.23%, 4.34%, 6.68%, 7.14%, -5.56%, -5.23%, -5.73%, -10.34%
98. Referring to Table 3-5, compute the arithmetic mean rate of return.
ANWER: 2.48%
TYPE: PR DIFFICULTY: Easy KEYWORDS: arithmetic mean
99. Referring to Table 3-5, what is the range of the rate of return?
ANSWER: 18.55%
TYPE: PR DIFFICULTY: Easy KEYWORDS: range
100. Referring to Table 3-5, construct a boxplot for the rate of return.
Box-and-whisker Plot -0.15-0.1-0.0500.050.1ANSWER:
TYPE: PR DIFFICULTY: Easy KEYWORDS: boxplot
101. Referring to Table 3-5, what is the shape of the distribution for the rate of return?
ANSWER: Left-skewed
TYPE: PR DIFFICULTY: Easy KEYWORDS: shape
TABLE 3-6
Copyright ? 2010 Pearson Education, Inc. Publishing as Prentice Hall
Numerical Descriptive Measures 95
The rate of return of an Internet Service Provider over a 10 year period are: 10.25%, 12.64%, 8.37%, 9.29%, 6.23%, 42.53%, 29.23%, 15.25%, 21.52%, -2.35%.
102. Referring to Table 3-6, compute the arithmetic mean rate of return.
ANWER: 15.30%
TYPE: PR DIFFICULTY: Easy KEYWORDS: arithmetic mean
103. Referring to Table 3-6, construct a boxplot for the rate of return
ANWER:
Box-and-whisker Plot -0.100.10.20.30.40.5TYPE: PR DIFFICULTY: Moderate KEYWORDS: boxplot
104. Referring to Table 3-6, what is the shape of the distribution for the rate of return?
ANSWER: Right-skewed
TYPE: PR DIFFICULTY: Moderate KEYWORDS: shape
105. The Z scores can be used to identify outliers.
ANSWER: True
TYPE: TF DIFFICULTY: Easy KEYWORDS: Z scores
106. The larger the Z score, the farther is the distance from the observation to the median.
Copyright ? 2010 Pearson Education, Inc. Publishing as Prentice Hall
96 Numerical Descriptive Measures
ANSWER: False
TYPE: TF DIFFICULTY: Moderate KEYWORDS: Z scores
107. As a general rule, an observation is considered an extreme value if its Z score is greater than??3.
ANSWER: False
TYPE: TF DIFFICULTY: Easy KEYWORDS: Z score
108. As a general rule, an observation is considered an extreme value if its Z score is greater than?3.
ANSWER: True
TYPE: TF DIFFICULTY: Easy KEYWORDS: Z score
109. As a general rule, an observation is considered an extreme value if its Z score is less than?3.
ANSWER: False
TYPE: TF DIFFICULTY: Easy KEYWORDS: Z score
110. As a general rule, an observation is considered an extreme value if its Z score is less than??3.
ANSWER: True
TYPE: TF DIFFICULTY: Easy KEYWORDS: Z score
111. The Z score of an observation can never be negative.
ANSWER: False
TYPE: TF DIFFICULTY: Moderate KEYWORDS: Z score
112. The Z score of an observation measures how many standard deviations is the value from the
mean.
ANSWER: True
TYPE: TF DIFFICULTY: Moderate KEYWORDS: Z score
Copyright ? 2010 Pearson Education, Inc. Publishing as Prentice Hall
Numerical Descriptive Measures 97
TABLE 3-7
Given below is the frequency distribution of the 12-month rate of return achieved by 30 stocks. 12-month Rate of Return Number of Funds 3 ?0.10 but less than 0.0 0.0 but less than 0.1 5 0.1 but less than 0.2 6 0.2 but less than 0.3 10 0.3 but less than 0.4 6
113. Referring to Table 3-7, what is the approximate mean rate of return?
ANSWER: 0.1867
TYPE: PR DIFFICULTY: Moderate KEYWORDS: approximate mean
114. Referring to Table 3-7, what is the approximate variance?
ANSWER: 0.0162
TYPE: PR DIFFICULTY: Moderate KEYWORDS: approximate variance
115. Referring to Table 3-7, what is the approximate standard deviation?
ANSWER: 0.1273
TYPE: PR DIFFICULTY: Moderate
KEYWORDS: approximate standard deviation
TABLE 3-8
Given below is the frequency distribution of the number of defective tomatoes in 50 different shipments. Defective Items Frequency 0 but less than 5 35 5 but less than 10 7 10 but less than 15 5 15 but less than 20 2 20 but less than 25 1 25 but less than 30 0 Copyright ? 2010 Pearson Education, Inc. Publishing as Prentice Hall
98 Numerical Descriptive Measures
116. Referring to Table 3-8, what is the approximate mean number of defective tomatoes?
ANSWER: 5.2
TYPE: PR DIFFICULTY: Moderate KEYWORDS: approximate mean
117. Referring to Table 3-8, what is the approximate variance?
ANSWER: 23.6837
TYPE: PR DIFFICULTY: Moderate KEYWORDS: approximate variance
118. Referring to Table 3-8, what is the approximate standard deviation?
ANSWER: 4.8666
TYPE: PR DIFFICULTY: Moderate
KEYWORDS: approximate standard deviation
TABLE 3-9
In the 2002–2003 academic year, many public universities in the United States raised tuition and fees due to a decrease in state subsidies. The change in the cost of tuition, a shared dormitory room, and the most popular meal plan from the 2001–2002 academic year for a sample of 10 public universities were as follows: $1589, $593, $1223, $869, $423, $1720, $708, $1425, $922 and $308.
119. Referring to Table 3-9, what is the mean and median change in the cost?
ANSWER: $978, $895.5
TYPE: PR DIFFICULTY: Moderate KEYWORDS: mean
120. Referring to Table 3-9, what are the five-number summary of the change in the cost?
ANSWER:
$308, $593, $895.5, $1425, and $1720 TYPE: PR DIFFICULTY: Moderate KEYWORDS: five-number summary
121. Referring to Table 3-9, what is the standard deviation of the change in the cost?
ANSWER: $491.8
TYPE: PR DIFFICULTY: Moderate KEYWORDS: standard deviation
Copyright ? 2010 Pearson Education, Inc. Publishing as Prentice Hall