The following table lists a portion of U.S. life expectancy (in years) for the 50 states.
Find the mean, the median, and the mode of life expectancy.
Rank State Life Expectancy 1 Hawaii 81.5 2 Alaska 80.9 50 Mississippi 74.8
> Consider a sample with six observations of 6, 9, 12, 10, 9, and 8. Compute the z-scores for each sample observation.
> The accompanying data file shows the Fortune 500 rankings of America’s largest corporations for 2010. Next to each corporation are its market capitalization (in $ billions as of March 26, 2010) and its total return (in %) to investors for the year 2009.
> The Wall Street Journal (August 28, 2006) asked its readers: “Ideally, how many days a week, if any, would you work from home?” The following relative frequency distribution summarizes the responses from 3,478 readers. Days Working from Home ……………………………
> In order to get an idea on current buying trends, a real estate agent collects data on 10 recent house sales in the area. Specifically, she notes the number of bedrooms in each house as follows: a. Calculate the mean, the median, and the mode. b. Which
> Data are drawn from a bell-shaped distribution with a mean of 25 and a standard deviation of 4. There are 1,000 observations in the data set. a. Approximately what percentage of the observations are less than 33? b. Approximately how many observations a
> The accompanying table lists a portion of the ages and net worth (in $ billions) of the wealthiest people in America. a. What percentage of the wealthiest people in America had net worth more than $20 billion? b. What percentage of the wealthiest peop
> Consider a bell-shaped distribution with a mean of 750 and a standard deviation of 50. There are 500 observations in the data set. a. Approximately what percentage of the observations are less than 700? b. Approximately how many observations are less th
> A survey conducted by CBS News asked 1,026 respondents: “What would you do with an unexpected tax refund?” The responses (in %) are summarized in the following table. Pay off debts ……………………………………………………………………………….. 47 Put it in the bank ……………………………………………
> A recent poll of 3,057 individuals asked: “What’s the longest vacation you plan to take this summer?” The following relative frequency distribution summarizes the results. Response …………………………………………………………………… Relative Frequency A few days ………………………………………
> Money magazine (January 2007) reported that an average of 77 million adults in the United States make financial resolutions at the beginning of a new year. Consider the following frequency distribution, which reports the top financial resolutions of 1,02
> AnnArbor_Rental. Real estate investment in college towns continues to promise good returns (The Wall Street Journal, September 24, 2010). Marcela Treisman works for an investment firm in Michigan. Her assignment is to analyze the rental market in Ann Arb
> The Department of Transportation (DOT) fields thousands of complaints about airlines each year. The DOT categorizes and tallies complaints, and then periodically publishes rankings of airline performance. The following table presents the 2006 results for
> Consider the following sample data: a. Calculate the range. b. Calculate MAD. c. Calculate the sample variance. d. Calculate the sample standard deviation. 40 48 32 52 38 42
> Consider the following observations for a time series: a. Calculate the growth rates for Year 1–Year 2, Year 2–Year 3, and Year 3–Year 4. b. Calculate the average growth rate. Year 1 Year 2 Yea
> A 2003 survey by the Centers for Disease Control and Prevention concluded that smoking is forbidden in nearly 75% of U.S. households (The Boston Globe, May 25, 2007). The survey gathered responses from at least 900 households in each state. When resident
> Fifty pro-football rookies were rated on a scale of 1 to 5, based on performance at a training camp as well as on past performance. A ranking of 1 indicated a poor prospect whereas a ranking of 5 indicated an excellent prospect. The following frequency d
> A researcher conducts a mileage economy test involving 80 cars. The frequency distribution describing average miles per gallon (mpg) appears in the following table. Average mpg …………………………………………………………………………… Frequency 15 up to 20 ………………………………………………………………
> In an attempt to determine whether a relationship exists between the price of a home (in $1,000s) and the number of days it takes to sell the home, a real estate agent collects data on the recent sales of eight homes. Price ……………………………………………………………………………
> In order to diversify risk, investors are often encouraged to invest in assets whose returns have either a negative relationship or no relationship. The annual return data (in %) on two assets is shown in the accompanying table. Return A ………………………………………
> A study offers evidence that the more weight a woman gains during pregnancy, the higher the risk of having a high-birth-weight baby, defined as at least 8 pounds, 13 ounces, or 4 kilograms (The Wall Street Journal, August 5, 2010). High-birth-weight babi
> A statistics instructor wants to examine whether a relationship exists between the hours a student spends studying for the final exam (Hours) and a student’s grade on the final exam (Grade). She takes a sample of eight students. Const
> Construct a scatterplot with the following data. Describe the relationship between x and y. X 1 2 3 4 5 7 8 y 22 20 18 10 4 3 2 LO
> Construct a scatterplot with the following data. Does a linear relationship exist between x and y? 10 4 3 7 y 3 2 6 6 4
> Construct a scatterplot with the following data. Describe the relationship between x and y. 3 7 12 6. y 22 10 5 14 12
> Consider the following sample data: a. Calculate the range. b. Calculate MAD. c. Calculate the sample variance sample standard deviation. -10 12 -8 -2 -6
> A police officer is concerned with excessive speeds on a portion of Interstate 90 with a posted speed limit of 65 miles per hour. Using his radar gun, he records the following speeds for 25 cars and trucks: Construct a stem-and-leaf diagram. Are the of
> Consider the following population data: a. Calculate the range. b. Calculate MAD. c. Calculate the population variance. d. Calculate the population standard deviation. -4 2 -8 10
> What is the minimum sample size n required to estimate p with 95% confidence if the desired margin of error E = 0.08? The population proportion is estimated as from prior studies. What happens to n if the desired margin of error increases to E = 0.12?
> Go to www.finance.yahoo.com/ to get a current stock quote for General Electric, Co. (ticker symbol = GE). Then, click on historical prices to record the monthly adjusted close price of General Electric stock in 2016. Create a table that uses this informa
> AccuWeather.com reported the following weather delays at these major U.S. airline hubs for July 21, 2010: a. Construct frequency and relative frequency distributions that summarize the delays at major U.S. hubs. What was the most common type of delay?
> Consider the following population data: a. Calculate the range. b. Calculate MAD. c. Calculate the population variance. d. Calculate the population standard deviation. 34 42 12 10 22
> The following table shows sales for Nike (in $ millions) for the years 2011 through 2015. a. Use the growth rates for 2011–2012, 2012–2013, 2013–2014, and 2014–2015 to calculate th
> The following table shows the total revenue (in $ billions) for Walmart Stores, Inc., and Target Corp. for the years 2008–2010. a. Calculate the average growth rate for each firm. b. Which firm had the higher growth rate over the 200
> The returns for an auto firm are 5% in Year 1 and 3% in the first quarter of Year 2. Calculate the annualized return for the period.
> Home Depot and Lowe’s are the two largest home improvement retailers in the U.S. The following table shows the total revenue (in $ billions) for each retailer for the years 2008– 2010. a. Calculate the growth rate fo
> The returns for a pharmaceutical firm are 10% in Year 1, 5% in Year 2, and −15% in Year 3. What is the annualized return for the period?
> Calculate the average growth rate from the following growth rates. 2.5% 3.6% 1.8% 2.2% 5.2%
> Consider the following observations for a time series: a. Calculate the growth rates for Year 1–Year 2, Year 2–Year 3, and Year 3–Year 4. b. Calculate the average growth rate. Year 1 Year 2 Yea
> The following histogram summarizes the salaries (in $1,000,000s) for the 30 highest-paid players in the National Basketball Association (NBA) for the 2012 season (www.nba.com, data retrieved March 2012). a. Is the distribution symmetric? If not, is it
> In the planning stage, a sample proportion is estimated as . Use this information to compute the minimum sample size n required to estimate p with 99% confidence if the desired margin of error E = 0.12. What happens to n if you decide to estimate p with
> The following histogram summarizes Apple Inc.’s monthly stock price for the years 2007 through 2011 (http://finance.yahoo.com, data retrieved April 20, 2012). a. Is the distribution symmetric? If not, is it positively or negatively sk
> A survey asked chief executives at leading U.S. firms the following question: “Where do you expect the U.S. economy to be 12 months from now?” A representative sample of their responses appears below: a. Construct f
> The returns from an investment are 2% in Year 1, 5% in Year 2, and 1.8% in the first half of Year 3. Calculate the annualized return for the entire period.
> The following relative frequency histogram summarizes the median household income for the 50 states in the United States (U.S. Census, 2010). Is the distribution symmetric? If not, is it positively or negatively skewed? What percentage of the states ha
> Given the following investment returns, calculate the geometric mean return. -3% 2% -5% 2.7% 3.1%
> Given the following investment returns, calculate the geometric mean return 4% 8% -5% 6%
> Given the following observations from a population, calculate the mean, the median, and the mode. 20 15 25 20 10 15 25 20 15
> Given the following observations from a population, calculate the mean, the median, and the mode. 150 257 55 110 110 43 201 125 55
> Given the following observations from a sample, calculate the mean, the median, and the mode. -4 -6 -3 -4
> What is the minimum sample size n required to estimate μ with 90% confidence if the desired margin of error is E = 1.2? The population standard deviation is estimated as. What happens to n if the desired margin of error decreases to E = 0.7?
> Consider the following cumulative relative frequency distribution. Class …………………………………………………………….. Cumulative Relative Frequency 150 up to 200 ………………………………………………………………………………………. 0.10 200 up to 250 ………………………………………………………………………………………. 0.35 250 up to 300 ……
> Gas_Prices_2012. The accompanying table shows a portion of the average price of gas (in $ per gallon) for the 50 states in the United States. State …………………………………………………………………………………………… Price Alabama ……………………………………………………………………………………… 4.36 Alaska ………………………
> First-time patients at North Shore Family Practice are required to fill out a questionnaire that gives the doctor an overall idea of each patient’s health. The first question is: “In general, what is the quality of you
> Consider the following boxplot a. Does the boxplot indicate possible outliers in the data? b. Comment on the skewness of the underlying distribution. 1.5 IQR 1.5 IQR
> Consider the following boxplot a. Does the boxplot indicate possible outliers in the data? b. Comment on the skewness of the underlying distribution. 1.5 IQR 1.5 IQR
> One important statistic in baseball is a pitcher’s earned run average, or ERA. This number represents the average number of earned runs given up by the pitcher per nine innings. The following table lists a portion of the ERAs for pitche
> Given the following observations from a sample, calculate the mean, the median, and the mode. 8 10 9 12 12
> Consider the following data set: a. Construct the frequency distribution using classes of 3 up to 5, 5 up to 7, etc. b. Construct relative frequency, cumulative frequency, and cumulative relative frequency distributions. c. How many of the observation
> Annual sales at a small pharmaceutical firm have been rather stagnant over the most recent five-year period, exhibiting only 1.2% growth over this time frame. A research analyst prepares the accompanying graph for inclusion in a sales report. Does this
> The following table shows a portion of the sale price (in $1,000s) for 36 homes sold in Mission Viejo, CA, during June 2010. Number …………………………………………………………………………………………. Price 1 ……………………………………………………………………………………………………… 430 2 …………………………………………………………………………………
> Data are drawn from a bell-shaped distribution with a mean of 20 and a standard deviation of 2. a. Approximately what percentage of the observations fall between 18 and 22? b. Approximately what percentage of the observations fall between 16 and 24? c. A
> The accompanying figure plots the monthly stock price of Caterpillar, Inc., from July 2009 through March 2011. The stock has experienced tremendous growth over this time period, almost tripling in price. Does the figure reflect this growth? If not, why n
> In a USA TODAY/Gallup Poll, respondents favored Barack Obama over Mitt Romney in terms of likeability, 60% to 30% (Los Angeles Times, July 28, 2012). The following bar chart summarizes the responses. a. What percentage of respondents favored neither Ob
> A professor records the majors of her 30 students as follows: a. What is the measurement scale of these data? b. Summarize the results in tabular form. c. What information can be extracted from the data? Accounting Economics Undecided Finance Man
> In each of the following scenarios, define the type of measurement scale. a. A meteorologist records the amount of monthly rainfall over the past year. b. A sociologist notes the birth year of 50 individuals. An investor monitors the daily stock price
> In each of the following scenarios, define the type of measurement scale. a. An investor collects data on the weekly closing price of gold throughout a year. b. An analyst assigns a sample of bond issues to one of the following credit ratings, given in
> In each of the following scenarios, define the type of measurement scale. a. A kindergarten teacher marks whether each student is a boy or a girl. b. A ski resort records the daily temperature during the month of January. c. A restaurant surveys its cu
> Which of the following variables are qualitative and which are quantitative? If the variable is quantitative, then specify whether the variable is discrete or continuous. a. Colors of cars in a mall parking lot. b. Time it takes each student to complete
> Which of the following variables are qualitative and which are quantitative? If the variable is quantitative, then specify whether the variable is discrete or continuous. a. Points scored in a football game. b. Racial composition of a high school class
> Conduct an online search for a weekly car rental in Seattle, Washington, and Portland, Oregon, for different car types and rental car companies for the year 2017. Are the data structured or unstructured? Are the data cross-sectional or time series?
> Ask your peers about their online social media usage. In particular collect information on (a) whether they use Facebook, Instagram, and Snapchat, (b) how often they use each social media service, and (c) their overall satisfaction with each of these ser
> A data set has a mean of 500 and a standard deviation of 25. a. Using Chebyshev’s theorem, find the interval that encompasses at least 75% of the data. b. Using Chebyshev’s theorem, find the interval that encompasses at least 89% of the data.
> Conduct an online search to compare price and fuel economy of small hybrid vehicles such as Toyota Prius, Ford Fusion, and Chevrolet Volt. Would the resulting data be structured or unstructured? Explain
> Go to The New York Times website at www.nytimes.com/ and review the front page. Would you consider the data on the page to be structured or unstructured? Explain.
> An investor bought common stock of Apple Inc. on three occasions at the following prices. Date Price …………………………………………………………………………………… Per Share January 2016 …………………………………………………………………………………….. 94.81 July 2016 ………………………………………………………………………………………… 102.67 Dec
> A local restaurant is committed to providing its patrons with the best dining experience possible. On a recent survey, the restaurant asked patrons to rate the quality of their entrées. The responses ranged from 1 to 5, where 1 indicated a d
> The significant decline of savings in the United States from the 1970s and 1980s to the 1990s and 2000s has been widely discussed by economists (www.money.cnn.com, June 30, 2010). According to the Bureau of Economic Analysis, the savings rate of American
> The following table lists a portion of U.S. life expectancy (in years) for the 50 states. Life Expectancy by State, 2010–2011 Source: en.wikipedia.org/wiki/List_of_U.S._states_by_life_expectancy, data retrieved April 25, 2012. In a r
> There are six broad sectors that comprise the Dow Jones Industrial Average (DJIA). These are the areas in which the company conducts its primary business. The following table shows a portion of the 30 companies that comprise the DJIA and each company’s s
> Research suggests that depression significantly increases the risk of developing dementia later in life (BBC News, July 6, 2010). In a study involving 949 elderly persons, it was reported that 22% of those who had depression went on to develop dementia,
> Business graduates in the United States with a marketing concentration earn high salaries. According to the Bureau of Labor Statistics, the average annual salary for marketing managers was $140,660 in 2015. a. What is the relevant population? b. Do you
> Many people regard video games as an obsession for youngsters, but, in fact, the average age of a video game player is 35 years (Reuters.com, August 21, 2009). Is the value 35 likely the actual or the estimated average age of the population? Explain
> The minimum and maximum observations in a population are 20 and 80, respectively. What is the minimum sample size n required to estimate μ with 80% confidence if the desired margin of error is E = 2.6? What happens to n if you decide to estimate μ with 9
> It came as a big surprise when Apple’s touch screen iPhone 4, considered by many to be the best smartphone ever, was found to have a problem (The New York Times, June 24, 2010). Users complained of weak reception, and sometimes even dropped calls, when t
> Thirty-three percent of children and teens in the United States are obese or overweight (Health, October 2010). A health practitioner in the Midwest collects data on 200 children and teens and finds that 84 of them are either obese or overweight. a. The
> An entrepreneur examines monthly sales (in $1,000s) for 40 convenience stores in Rhode Island. a. State the null and the alternative hypotheses in order to test whether average sales differ from $130,000. b. Calculate the value of the test statistic and
> On average, Americans drive 13,500 miles per year (The Boston Globe, June 7, 2012). An economist gathers data on the driving habits of 50 residents in the Midwest. a. The economist believes that the average number of miles driven annually by Midwesterner
> Using data from the past 25 years, an investor wants to test whether the average return of Vanguard’s Precious Metals and Mining Fund is greater than 12%. Assume returns are normally distributed with a population standard deviation of 30%. a. State the n
> A survey finds that 17% of Americans cannot part with their landlines (The Washington Post, February 27, 2014). A researcher in the rural South collects data from 200 households and finds that 45 of them still have landlines. a. The researcher believes t
> A television network is deciding whether or not to give its newest television show a spot during prime viewing time at night. For this to happen, it will have to move one of its most viewed shows to another slot. The network conducts a survey asking its
> A national survey found that 33% of high school students said they texted or e-mailed while driving (The Boston Globe, June 8, 2012). These findings came a day after a Massachusetts teenager was convicted for causing a fatal crash while texting. A resear
> A retailer is looking to evaluate its customer service. Management has determined that if the retailer wants to stay competitive, then it will have to have at least a 90% satisfaction rate among its customers. Management will take corrective actions if t
> A phone manufacturer wants to compete in the touch screen phone market. He understands that the lead product has a battery life of just 5 hours. The manufacturer claims that while the new touch screen phone is more expensive, its battery life is more tha
> One in five 18-year-old Americans has not graduated from high school (The Wall Street Journal, April 19, 2007). A mayor of a North-eastern city comments that its residents do not have the same graduation rate as the rest of the country. An analyst from t
> With increasing out-of-pocket healthcare costs, it is claimed that more than 60% of senior citizens are likely to make serious adjustments to their lifestyle. Test this claim at the 1% level of significance if in a survey of 140 senior citizens, 90 repor
> Construct the null and the alternative hypotheses for the following claims: a. “I am going to get the majority of the votes to win this election.” b. “I suspect that your 10-inch pizzas are, on average, less than 10 inches in size.” c. “I will have to fi
> A politician claims that he is supported by a clear majority of voters. In a recent survey, 24 out of 40 randomly selected voters indicated that they would vote for the politician. Is the politician’s claim justified at the 5% level of significance?
> Research shows that many banks are unwittingly training their online customers to take risks with their passwords and other sensitive account information, leaving them more vulnerable to fraud (Yahoo.com, July 23, 2008). Even web-savvy surfers could find
> In order to endure financial hardships such as unemployment and medical emergencies, Americans have increasingly been raiding their already fragile retirement accounts (MSN Money, July 16, 2008). It is reported that between 1998 and 2004, about 12% of fa
> A study by Allstate Insurance Co. finds that 82% of teenagers have used cell phones while driving (The Wall Street Journal, May 5, 2010). In October 2010, Massachusetts enacted a law that forbids cell phone use by drivers under the age of 18. A policy an