Business Stats - MidTerm
In a stem-and-leaf display, the leaf represents the members of a class in a frequency distribution. T/F
True
Pearson's coefficient of skewness is a measure of a distribution's symmetry. T/F
True
Statistics are used to report the summary results of market surveys. T/F
True
Statistics is defined as a body of techniques used to facilitate the collection, organization, presentation, analysis and interpretation of information for the purpose of making better decisions. T/F
True
The arithmetic mean is the sum of the quantitative observations divided by the total number of observations. T/F
True
The joint probability of two independent events, A and B, is computed as: P(A and B) = P(A) P(B). T/F
True
The probability of rolling a 3 or 2 on a single die is an example of mutually exclusive events. T/F
True
To infer something about a population, we usually take a sample from the population. T/F
True
A graphical method used to calculate joint and conditional probabilities is a tree diagram. a Venn diagram. a histogram. inferential statistics.
a tree diagram
When an event's probability depends on the likelihood of another event, the probability is a(n) conditional probability. empirical probability. joint probability. mutually exclusive probability.
conditional probability
If the variance of the "number of daily parking tickets issued" is 100, the variance is defined as: "number of daily parking tickets". "number of daily parking tickets" squared. the absolute value of the "number of daily parking tickets". the square root of the "number of daily parking tickets".
"number of daily parking tickets" squared
For a sample of similar sized all-electric homes, the March electric bills were (to the nearest dollar): $212, $191, $176, $129, $106, $92, $108, $109, $103, $121, $175 and $194. What is the range? $100 $130 $120 $112
$120
The following are the weekly amounts of welfare payments made by the federal government to a sample of six families: $139, $136, $130, $136, $147 and $136. What is the range? $0 $14 $52 $17
$17
A sample of the paramedical fees charged by clinics revealed these amounts: $55, $49, $50, $45, $52 and $55. What is the median charge? $47.50 $51.00 $52.00 $55.00
$51.00
A group of 100 students was surveyed about their interest in a new International Studies program. Interest was measured in terms of high, medium, or low. 30 students responded high interest; 40 students responded medium interest; 30 students responded low interest. What is the relative frequency of students with high interest? .30 .50 .40 Cannot be determined.
.30
When applying the special rule of addition for mutually exclusive events, the joint probability is: 1 .5 0
0
A sample of experienced typists revealed that their mean typing speed is 87 words per minute and the median is 73. The standard deviation is 16.9 words per minute. What is the Pearson's coefficient of skewness?-2.5 -4.2 +4.2 +2.5
+2.5
A group of employees of Unique Services will be surveyed about a new pension plan. In-depth interviews with each employee selected in the sample will be conducted. The employees are classified as follows. https://learn.vccs.edu/courses/1/NV280.BUS.220.E50W.SP19/ppg/129862947993706/image007.png What is the probability that the first person selected is a supervisor and in management? 0.00 0.06 0.15 0.21
0.00
A group of employees of Unique Services will be surveyed about a new pension plan. In-depth interviews with each employee selected in the sample will be conducted. The employees are classified as follows. https://learn.vccs.edu/courses/1/NV280.BUS.220.E50W.SP19/ppg/129862947993706/image004.png What is the probability that the first person selected is classified as a maintenance employee? 0.20 0.50 0.025 1.00
0.025
Each salesperson in a large department store chain is rated on their sales ability and their potential for advancement. The data for the 500 sampled salespeople are summarized in the following table. https://learn.vccs.edu/courses/1/NV280.BUS.220.E50W.SP19/ppg/129862947993706/image010.png What is the probability that a salesperson selected at random will have below average sales ability and fair potential for advancement? 0.032 0.10 0.16 0.32
0.032
In a management trainee program, 80 percent of the trainees are female, 20 percent male. Ninety percent of the females attended college, 78 percent of the males attended college. A management trainee is selected at random. What is the probability that the person selected is a male who did NOT attend college? 0.044 0.440 0.256 0.801
0.044
A group of employees of Unique Services will be surveyed about a new pension plan. In-depth interviews with each employee selected in the sample will be conducted. The employees are classified as follows. https://learn.vccs.edu/courses/1/NV280.BUS.220.E50W.SP19/ppg/129862947993706/image005.png What is the probability that the first person selected is either in maintenance or in secretarial? 0.200 0.015 0.059 0.001
0.059
In a management trainee program, 80 percent of the trainees are female, 20 percent male. Ninety percent of the females attended college, 78 percent of the males attended college. A management trainee is selected at random. What is the probability that the person selected is a female who did NOT attend college? 0.20 0.08 0.25 0.80
0.08
Each salesperson in a large department store chain is rated on their sales ability and their potential for advancement. The data for the 500 sampled salespeople are summarized in the following table. https://learn.vccs.edu/courses/1/NV280.BUS.220.E50W.SP19/ppg/129862947993706/image009.png What is the probability that a salesperson selected at random will have average sales ability and good potential for advancement? 0.09 0.12 0.30 0.525
0.12
A study of 200 computer service firms revealed these incomes after taxes: https://learn.vccs.edu/courses/1/NV280.BUS.220.E50W.SP19/ppg/129862947993706/image002.png What is the probability that a particular firm selected has $1 million or more in income after taxes? 0.00 0.25 0.49 0.51
0.49
A study by the National Park Service revealed that 50% of the vacationers going to the Rocky Mountain region visit Yellowstone Park, 40% visit the Grand Tetons and 35% visit both. What is the probability that a vacationer will visit at least one of these magnificent attractions?0.95 0.35 0.55 0.05
0.55
In a finance class, the final grade is based on three tests. Historically, the instructor tells the class that the joint probability of scoring "A"'s on the first two tests is 0.5. A student assigns a probability of 0.9 that she will get an "A" on the first test. What is the probability that the student will score an "A" on the second test given that she scored an "A" on the first test? 0.50 0.95 0.55 0.90
0.55
In a management trainee program, 80 percent of the trainees are female, 20 percent male. Ninety percent of the females attended college, 78 percent of the males attended college. A management trainee is selected at random. What is the probability that the person selected is a female who did attend college? 0.20 0.08 0.25 0.72
0.72
A study of interior designers' opinions with respect to the most desirable primary color for executive offices showed that: https://learn.vccs.edu/courses/1/NV280.BUS.220.E50W.SP19/ppg/129862947993706/image013.png What is the probability that a designer does not prefer red? 1.00 0.77 0.73 0.23
0.77
A tire manufacturer advertises, "the median life of our new all-season radial tire is 50,000 miles. An immediate adjustment will be made on any tire that does not last 50,000 miles." You purchased four of these tires. What is the probability that all four tires will wear out before traveling 50,000 miles? 1/10 or 0.10 ¼ or 0.25 1/64 or 0.0156 1/16 or 0.0625
1/16 or 0.0625
The test scores for a class of 147 students are computed. What is the location of the test score associated with the third quartile? 111 37 74 75%
111
The Investment Research Institute reported in its Mutual Fund Fact Book that the number of mutual funds increased from 5725 in 1999 to 7977 in 2009. What is the geometric mean annual percent increase in the number of funds? 1.034 3.37 39.34 71.77 633.5
3.37
Quartiles divide a distribution into: 2 equal parts. 4 equal parts. 10 equal parts. 100 equal parts.
4 equal parts
The numbers 0 through 9 are used in code groups of four to identify an item of clothing. Code 1083 might identify a blue blouse, size medium. The code group 2031 might identify a pair of pants, size 18, and so on. Repetitions of numbers are not permitted, i.e., the same number cannot be used more than once in a total sequence. As examples, 2256, 2562 or 5559 would not be permitted. How many different code groups can be designed? 5,040 620 10,200 120
5,040
You have the assignment of designing color codes for different parts. Three colors are used on each part, but a combination of three colors used for one part cannot be rearranged and used to identify a different part. This means that if green, yellow and violet were used to identify a camshaft, yellow, violet and green (or any other combination of these three colors) could not be used to identify a pinion gear. If there are 35 combinations, how many colors were available? 5 7 9 11
7
Probabilities are important information when using inferential statistics. applying descriptive statistics. predicting a future outcome. A and C
A and C
What level of measurement is a person's "favorite sport"? Ratio Ordinal Interval Nominal
Nominal
A sample of assistant professors on the business faculty at state supported institutions in Ohio revealed the mean income to be $72,000 for 9 months with a standard deviation of $3,000. Using Chebyshev's Theorem, what proportion of the faculty earns more than $66,000 but less than $78,000? At least 50% At least 25% At least 75% At least 100%
At least 75%
A student was interested in the cigarette smoking habits of college students and collected data from an unbiased random sample of students. The data is summarized in the following table: https://learn.vccs.edu/courses/1/NV280.BUS.220.E50W.SP19/ppg/129864603395371/image002.png What type of chart best represents the frequency table? Bar Chart Pie Chart Scatter plot Frequency Polygon
Bar Chart
The following graph is a https://learn.vccs.edu/courses/1/NV280.BUS.220.E50W.SP19/ppg/129864606018743/image005.png Dot plot Stem-and-leaf display Box plot Contingency table
Box Plot
What type of variable is the number of gallons of gasoline pumped by a filling station during a day?Qualitative Continuous Attribute Discrete
Continuous
A value that is typical or representative of the data is referred to as a measure of central location.. T/F
True
A dot plot is an easy way to represent the relationship between two variables.. T/F
False
A listing of 100 family annual incomes is an example of statistics. T/F
False
A scatter diagram of sales versus production may be constructed by plotting the minimum, first quartile, median, third quartile, and the maximum values of each variable. T/F
False
According to Chebyshev's Theorem, 75% percent of the observations lie within plus and minus 2.00 average mean deviations. T/F
False
Categorizing voters as Democrats, Republicans and Independents is an example of interval level measurement. T/F
False
Descriptive statistics are used to find out something about a population based on a sample. T/F
False
For any distribution, there are an equal number of values above and below the mean. T/F
False
If two events are mutually exclusive, then P(A or B) = P(A) P(B). T/F
False
Quartiles divide a distribution into ten equal parts. T/F
False
The probability of rolling a 3 or 2 on a single die is an example of conditional probability.. T/F
False
The relative frequency for a class is computed as the class width divided by class interval. midpoint divided by the class frequency. frequency divided by the class interval. frequency divided by the total frequency.
Frequency divided by the total frequency
What level of measurement is the Centigrade temperature scale? Nominal Ordinal Interval Ratio
Interval
The reported unemployment is 5.5% of the population. What measurement scale is used to measure unemployment? Nominal Ordinal Interval or ratio Descriptive
Interval or Ratio
The sum of the deviations of each data value from this measure of central location will always be zero. Mode Mean Median Standard deviation
Mean
For any data set, which measures of central location have only one value? Mode and median Mode and mean Mode and standard deviation Mean and median
Mean and Median
For a data set, half of the observations are always greater than the: Median Mode Mean Standard deviation
Median
Which measures of central location are not affected by extremely small or extremely large values? Mean and median Mean and mode Mode and median Standard deviation and mean
Mode and Median
If Gallup, Harris and other pollsters asked people to indicate their political party affiliation as Democrat, Republican or Independent, the data gathered would be an example of which scale of measurement?Nominal Ordinal Interval Ratio
Nominal
The Equal Employment Opportunity Act requires employers to classify their employees by gender and national origin. Which level of measurement is this?Nominal Ordinal Interval Ratio
Nominal
When a class interval is expressed as: 100 up to 200, Observations with values of 100 are excluded from the class. Observations with values of 200 are included in the class. Observations with values of 200 are excluded from the class. The class interval is 99.
Observations with values of 200 are excluded from the class
What is the lowest level of measurement that a median can be computed? Nominal Ordinal Interval Ratio
Ordinal
In a management trainee program, 80 percent of the trainees are female, 20 percent male. Ninety percent of the females attended college, 78 percent of the males attended college. A management trainee is selected at random. What is the probability that the person selected is a male who did NOT attend college? P (male) P (did not attend college | male) P (did not attend college) P (male | did not attend college) P (male) P (did not attend college) P (did not attend college)
P (male) P (did not attend college | male)
What does the complement rule state? P(A) = P(A) - P(B) P(A) = 1 - P(not A) P(A) = P(A) · P(B) P(A) = P(A)X + P(B)
P(A) = 1 - P(not A)
A group of 100 students were surveyed about their interest in a new Economics major. Interest was measured in terms of high, medium, or low. 30 students responded high interest; 50 students responded medium interest; 20 students responded low interest. What is the best way to illustrate the relative frequency of student interest? Cumulative frequency polygon Bar chart Pie chart Frequency table
Pie Chart
What type of variable is the number of robberies reported in your city? Attribute Continuous Quantitative Qualitative
Quantitative
Monthly commissions of first-year insurance brokers are $1,270, $1,310, $1,680, $1,380, $1,410, $1,570, $1,180 and $1,420. These figures are referred to as: histogram. raw data. frequency distribution. frequency polygon.
Raw Data
What is a portion or part of a population called?Random survey Sample Tally Frequency distribution
Sample
Based on a sample of 3,000 people, the civilian unemployment rate in the United States was 5.5%. 5.5% is referred to as a statistic. T/F
True
The general process of gathering, organizing, summarizing, analyzing, and interpreting data is called: Statistics. Descriptive statistics. Inferential statistics. Levels of measurement.
Statistics
The following graph is a https://learn.vccs.edu/courses/1/NV280.BUS.220.E50W.SP19/ppg/129864606018743/image002.png Dot plot Stem-and-leaf display Box plot Contingency table
Stem-and-leaf display
The main purpose of descriptive statistics is to: Summarize data in a useful and informative manner. Make inferences about a population. Determine if the data adequately represents the population. Gather or collect data.
Summarize data in a useful and informative manner
A student was studying the political party preferences of a university's student population. The survey instrument asked students to identify themselves as a democrat or a republican. This question is flawed because: Students generally don't know their political preferences. The categories are generally mutually exclusive. The categories are not exhaustive. Political preference is a continuous variable.
The categories are not exhaustive
A dot plot can be used to show: The mean, median and mode. The general shape of a distribution for a nominal qualitative variable. The distribution for a quantitative variable. The interquartile range.
The distribution for a quantitative variable
A dot plot shows the: The general shape of a distribution. The mean, median, and mode. The relationship between two variables. The interquartile range.
The general shape of a distribution
A stem-and-leaf display includes the following row: 3 | 0 1 3 5 7 9. Assume that the data is rounded to the nearest whole number. The frequency of the class is seven. The minimum value in the class is 0. The maximum value in the class is 39. The class interval is 5.
The maximum value in the class is 39
What does the interquartile range describe? The lower 50% of the observations The middle 50% of the observations The upper 50% of the observations The lower 25% and the upper 25% of the observations
The middle 50% of the observations
Why are unequal class intervals sometimes used in a frequency distribution? To avoid a large number of empty classes For the sake of variety in presenting the data To make the class frequencies smaller To avoid the need for midpoints
To avoid a large number of empty classes
Which of the following is an example of a continuous variable? Tons of concrete to complete a parking garage Number of students in a statistics class Zip codes of shoppers Rankings of baseball teams in a league
Tons of concrete to complete a parking garage
A dot plot is useful for showing the range of the data. T/F
True
A dot plot shows the relative symmetry of a distribution. T/F
True
A frequency polygon is a very useful graphic technique when comparing two or more distributions. T/F
True
Refer to the following breakdown of responses to a survey of "Are you concerned about being tracked while connected to the Internet"? https://learn.vccs.edu/courses/1/NV280.BUS.220.E50W.SP19/ppg/129864603395371/image032.png What is the class with the greatest frequency? Very concerned Somewhat concerned No concern None of the above
Very Concerned
Refer to the following distribution of commissions: https://learn.vccs.edu/courses/1/NV280.BUS.220.E50W.SP19/ppg/129864603395371/image009.png The first coordinate for a cumulative frequency distribution would be: X = 0, Y = 500. X = 500, Y = 3. X = 3, Y = 600. X = 500, Y = 0.
X = 500, Y = 0
Sometimes, data has two values that have the highest and equal frequencies. In this case, the distribution of the data can best be summarized as: symmetric bimodal (having two modes) positively skewed negatively skewed
bimodal (having two modes)
What is the value of the Pearson coefficient of skewness for a distribution with a mean of 17, median of 12 and standard deviation of 6? +2.5 -2.5 +0.83 -0.83
+2.5
Refer to the following distribution of ages: https://learn.vccs.edu/courses/1/NV280.BUS.220.E50W.SP19/ppg/129864603395371/image016.png For the distribution of ages above, what is the relative class frequency for the lowest class? .50 .18 .20 .10
.20
The weights (in grams) of the contents of several small bottles are 4, 2, 5, 4, 5, 2 and 6. What is the sample variance? 6.92 4.80 1.96 2.33
2.33
Assume a student received the following grades for the semester: History, B; Statistics, A; Spanish, C; and English, C. History and English are 5 credit hour courses, Statistics a 4 credit hour course and Spanish a 3 credit hour course. If 4 grade points are assigned for an A, 3 for a B and 2 for a C, what is the weighted mean for the semester grades? 4.00 1.96 2.76 3.01
2.76
Refer to the following breakdown of responses to a survey of "Are you concerned about being tracked while connected to the Internet"? https://learn.vccs.edu/courses/1/NV280.BUS.220.E50W.SP19/ppg/129864603395371/image033.png What percent of the responses indicated that users were somewhat concerned? 40% 70% 20% 100%
20%
Refer to the following breakdown of responses to a survey of "How confident are you that you saved enough to retire"? https://learn.vccs.edu/courses/1/NV280.BUS.220.E50W.SP19/ppg/129864603395371/image038.png What percent of the responses indicated that users were very confident? 63% 21% 45% 33%
21%
Refer to the following frequency distribution on days absent during a calendar year by employees of a manufacturing company: https://learn.vccs.edu/courses/1/NV280.BUS.220.E50W.SP19/ppg/129864603395371/image024.png How many employees were absent six days or more? 8 4 22 31
22
What is the median of 26, 30, 24, 32, 32, 31, 27 and 29?32 29 30 29.5
29.5
Refer to the following frequency distribution on days absent during a calendar year by employees of a manufacturing company: https://learn.vccs.edu/courses/1/NV280.BUS.220.E50W.SP19/ppg/129864603395371/image022.png How many employees were absent between 3 up to 6 days? 31 29 14 2
31
Refer to the following breakdown of responses to a survey of room service in a hotel. https://learn.vccs.edu/courses/1/NV280.BUS.220.E50W.SP19/ppg/129864603395371/image028.png What percent of the responses indicated that customers were satisfied? 40% 33% 50% 100%
33%
Ten experts rated a newly developed chocolate chip cookie on a scale of 1 to 50. Their ratings were: 34, 35, 41, 28, 26, 29, 32, 36, 38 and 40. What is the mean deviation? 8.00 4.12 12.67 0.75
4.12
Production of passenger cars in Japan increased from 3.94 million in 1999 to 6.74 million in 2009. What is the geometric mean annual percent increase? 4.0 1.9 5.5 16.6 47.3
5.5
Refer to the following distribution: https://learn.vccs.edu/courses/1/NV280.BUS.220.E50W.SP19/ppg/129864603395371/image020.png What is the class midpoint for the $45 up to $55 class?49 49.5 50 50.5
50
A dot plot is best applied for a data set with 1,000 observations. 50 observations. More than one variable. A one mode.
50 observations
The lengths of time (in minutes) several underwriters took to review applications for similar insurance coverage are: 50, 230, 52 and 57. What is the median length of time required to review an application? 54.5 141.0 97.25 109.0
54.5
Refer to the following information from a frequency distribution for "heights of college women" recorded to the nearest inch: The first two class midpoints are 62.5" and 65.5". What are the class limits for the lowest class? 61 and up to 64 62 and up to 64 62 and 65 62 and 63
61 and up to 64
A dot plot is best applied when: The mean, median and mode are equal. The general shape of a distribution is symmetric. The relationship between two variables is summarized. A single variable is summarized.
A single variable is summarized
Refer to the following breakdown of responses to a survey of "Are you concerned about being tracked while connected to the Internet"? https://learn.vccs.edu/courses/1/NV280.BUS.220.E50W.SP19/ppg/129864603395371/image034.png What type of chart should be used to describe the frequency table? Pie chart Bar chart Histogram Frequency Polygon
Bar Chart
Refer to the following breakdown of responses to a survey of "How confident are you that you saved enough to retire"? https://learn.vccs.edu/courses/1/NV280.BUS.220.E50W.SP19/ppg/129864603395371/image039.png What type of chart should be used to describe the frequency table? Pie chart Bar chart Histogram Frequency Polygon
Bar Chart
Refer to the following breakdown of responses to a survey of room service in a hotel. https://learn.vccs.edu/courses/1/NV280.BUS.220.E50W.SP19/ppg/129864603395371/image029.png What type of chart should be used to describe the frequency table? Pie chart Bar chart Histogram Frequency Polygon
Bar Chart
The age distribution of a sample of part-time employees at Lloyd's Fast Food Emporium is: https://learn.vccs.edu/courses/1/NV280.BUS.220.E50W.SP19/ppg/129864603395371/image006.png What type of chart should be drawn to present this data? Histogram Simple line chart Cumulative Frequency Distribution Pie chart Frequency polygon
Cumulative Frequency Distribution
In a company, the standard deviation of the ages of female employees is six years and the standard deviation of the ages of male employees is ten years. These statistics indicate that the dispersion of age is greater for females than for males. T/F
False
The 50th percentile of a distribution is the same as the distribution mean. T/F
False
The Union of Electrical Workers of America with 9,128 members polled 362 members about a new wage package that will be submitted to management. The population is the 362 members. T/F
False
The order that runners finish in a race would be an example of continuous data. T/F
False
To convert a frequency distribution to a relative frequency distribution, divide each class frequency by the number of classes. T/F
False
The following graph is https://learn.vccs.edu/courses/1/NV280.BUS.220.E50W.SP19/ppg/129864606018743/image006.png Positively skewed. Negatively skewed. Symmetric. Uniformly distributed.
Positively skewed
The Nielsen Ratings break down the number of people watching a particular television show by age. Age is what level of measurement? Nominal Ordinal Interval Ratio
Ratio
The incomes of a group of 50 loan applicants are obtained. Which level of measurement is income?Nominal Ordinal Interval Ratio
Ratio
A stem-and-leaf display includes the following row: 5 | 10 11 31 52 79 98. Assume that the data is rounded to the nearest whole number. The frequency of the class is seven. The minimum value in the class is 5. The maximum value in the class is 98. The class interval is 100.
The class interval is 100
What statistics are needed to draw a box plot? The minimum, maximum, median, first and third quartiles. The median, mean and standard deviation. The median and interquartile range. The mean and standard deviation.
The minimum, maximum, median, first and third quartiles
A pie chart is similar to a relative frequency distribution. T/F
True
A population is a collection of all individuals, objects, or measurements of interest.. T/F
True
A relationship between two nominal variables is summarized by a contingency table. T/F
True
A sample is a portion or part of the population of interest. T/F
True
The CIA World Factbook cited these numbers for the United States: • Birthrate is 14.14 births per 1,000 population • Average life expectancy for females is 80 years • Approximately 290 million persons residing in the United States Each of these numbers is referred to as statistic. T/F
True
The geometric mean is the nth root of n observations. T/F
True
The sum of the differences between sample observations and the sample mean is Zero The mean deviation The range The standard deviation
Zero
In a contingency table, we describe the relationship between: two variables measured at the ordinal or nominal level. two variables, one measured as an ordinal variable and the other as a ratio variable. two variables measured at the interval or ratio level. a variable measure on the interval or ratio level and time.
two variable measured at the ordinal or nominal level
