In Basketball players are awarded free throw when they are fouled. Suppose that a player has a career percentage of making free throws 80% of the time. If the player is awarded 10 free throws determine the probability of the following events. a. He makes all 10. b. He makes 8 or more. c. He makes 8 or fewer.
> Use a probability tree to compute the probability of the following events when flipping two fair coins. a. Heads on the first coin and heads on the second coin b. Heads on the first coin and tails on the second coin c. Tails on the first coin and heads o
> The average daily U.S. oil consumption and production (thousands of barrels) was recorded for the years 1973 to 2015. Draw a line chart for both sets of figures. Describe what you have learned.
> The costs of smoking for individuals, companies for whom they work, and society in general is in the many billions of dollars. In an effort to reduce smoking various government and non-government organizations have undertaken information campaigns about
> Interest on Federal Debt from 1935 to 2015 was recorded. draw the following line charts and briefly describe what the chart tells you about each variable. a. Original data b. Per capita data c. Per capita in constant 1982–1984 dollars
> Education spending from 1935 to 2015 was recorded. draw the following line charts and briefly describe what the chart tells you about each variable. a. Original data b. Per capita data c. Per capita in constant 1982–1984 dollars
> Welfare payments for 1965 to 2015 were recorded. draw the following line charts and briefly describe what the chart tells you about each variable. a. Original data b. Per capita data c. Per capita in constant 1982–1984 dollars
> Total Federal government spending from 1935 to 2015 is stored. draw the following line charts and briefly describe what the chart tells you about each variable. a. Original data b. Per capita data c. Per capita in constant 1982–1984 dollars
> The defense budget for years 1935 to 2015 were recorded. draw the following line charts and briefly describe what the chart tells you about each variable. a. Original data b. Per capita data c. Per capita in constant 1982–1984 dollars
> Social Insurance Old Age Survivor Insurance provides a pension for Americans who are over 60 years of age and whose spouse has died. Costs for 1958 to 2015 were recorded. draw the following line charts and briefly describe what the chart tells you about
> A statistics practitioner would like to draw a histogram of 40 observations that range from 5.2 to 6.1. a. How many class intervals should the histogram use? b. Define the upper limits of the classes.
> Social Security Disability Insurance a program that pays monthly benefits to individuals who have become disabled before reaching retirement age and aren’t able to work. SSDI costs were recorded for the years 1958 to 2015. draw the following line charts
> The probability that a university graduate will be offered no jobs within a month of graduation is estimated to be 5%. The probability of receiving one, two, and three job offers has similarly been estimated to be 43%, 31%, and 21%, respectively. Determi
> Medicaid is a program created by the federal government, but administered by the state, to provide payment for medical services for low-income citizens. The costs were recorded from 1962 to 2015. draw the following line charts and briefly describe what t
> Medicare Part B pays for a portion of physicians’ visits, medical equipment, outpatient procedures, rehabilitative therapy, laboratory tests, X-rays, ambulance service, and blood. Costs were recorded for 1967 to 2015. draw the following line charts and b
> The U.S. government provides Medicare to Americans who are 65 years and older. Medicare Part A pays the costs of hospital and nursing care, but not physicians’ bills. The file lists Medicare Part A costs since 1966. draw the following line charts and bri
> The United States spends more money on health care than any other country. To gauge how fast costs are rising we recorded the total health care costs since 1950. draw the following line charts and briefly describe what the chart tells you about each vari
> The number of violent crimes and the number of property crimes (burglary, larceny theft, and car theft) (in thousands) for the years 1993 to 2012 (latest figures available) are listed here. a. Draw a line chart of the violent crimes. b. Draw a line chart
> It won’t come as a surprise to hockey fans that with each passing season the number of goals scored is decreasing. Many experts blame goalie equipment. The oversized pads and other protection for goalies now makes even relatively small
> How well have Canada and the United States performed at the Winter Olympics? In the table displayed here, we list the total number of medals won by the two countries in each year. Draw a chart to describe both time series. Year Canada United States
> Respondents were asked to report the total value of certificates of deposit (CDs) in 2013 dollars held by the household. a. Try drawing histograms with different numbers of class intervals and different upper limits. b. What problem do you encounter in d
> One of the questions asked respondents to report the total value of assets held by the household in 2013 dollars. Note that the range is very large. The minimum is $0 and the maximum is $1,312,587,840. a. Draw a histogram using the number of class interv
> A data set consists of 300 observations that range between 147 and 241. a. What is an appropriate number of classes to have in the histogram? b. What class intervals would you suggest?
> A gambler believes that a strategy called “doubling up” is an effective way to gamble. The method requires the gambler to double the stake after each loss. Thus, if the initial bet is $1, after losing he will double the bet until he wins. After a win, he
> Create a histogram of the number of children. Despite the fact that the sample size is over 6,000, why should you not have 20 class intervals?
> Draw a histogram of the ages of the respondents in the 2013 survey. What information can you extract from the histogram?
> Among American adults with children draw a histogram of their ages when their first child was born (AGEKDBRN).
> Determine the number of classes of a histogram for 1500 observations.
> The lengths (in inches) of 150 newborn babies were recorded. Use whichever graphical technique you judge suitable to describe these data. What have you learned from the graph?
> The marks of 320 students on an economics midterm test were recorded. Use a graphical technique to summarize these data. What does the graph tell you?
> Users of previous editions of this book could download an Excel add-in called Data Analysis Plus from our website. We recorded the number of daily downloads during a 78-day period. a. Draw a histogram. b. Describe its shape.
> The following table lists the average oil consumption per day of the top 20 oil consuming nations. Use a graphical technique to display this information. Country Consumption of Oil (Barrels per Day) Australia
> Currently Ebay lists over 550,000 U.S. collector coins for sale or auction. An avid collector tracked the number of days it took for 500 coins to be sent to his home. Create a histogram of these figures. What information can you draw from the shape of th
> A survey of golfers asked the following questions. Identify the type of data each question produces. a. How many rounds of golf do you play annually? b. Are you a member of a private club? c. What brand of clubs do you own?
> An Internet pharmacy advertises that it will deliver the over-the-counter products that customers purchase in 3–6 days. The manager of the company wanted to be more precise in its advertising. Accordingly, she recorded the number of day
> Baseball fans are regularly asked to offer their opinions about various aspects of the sport. A survey asked the following questions. Identify the type of data. a. How many games do you attend annually? b. How would you rate the quality of entertainment?
> Information about a magazine’s readers is of interest to both the publisher and the magazine’s advertisers. A survey of readers asked respondents to complete the following: a. Age b. Gender c. Marital status d. Number of magazine subscriptions e. Annual
> A survey of the business school graduates undertaken by a university placement office asked, among other questions, in which area each person was employed. The areas of employment are as follows: 1. Accounting 2. Finance 3. General management 4. Marketin
> The annual incomes for a sample of 200 first-year accountants were recorded. Draw a histogram and describe its shape.
> There are several ways to teach applied statistics. The most popular approaches are as follows: 1. Emphasize manual calculations. 2. Use a computer combined with manual calculations. 3. Use a computer exclusively with no manual calculations. A survey of
> The Wilfrid Laurier University bookstore conducts annual surveys of its customers. One question asks respondents to rate the prices of textbooks. The wording is, “The bookstore’s prices of textbooks are reasonable.” The responses are as follows: 1. Stro
> Refer to Exercise 2.59. The percentage of uninsured in 2013 and 2014 in each of the 50 states plus District of Columbia was recorded. Use a graphical technique to show the decrease in the uninsured rate. Data from Exercise 2.59: The primary objective of
> A sample of shoppers at a mall was asked the following questions. Identify the type of data each question would produce. a. What is your age? b. How much did you spend? c. What is your marital status? d. Rate the availability of parking: excellent, good,
> The primary objective of the Affordable Care Act was to decrease the number of nonelderly without any health insurance. It is estimated that there are still approximately 40 million Americans without health insurance. Researchers asked a sample of them w
> The Consumer Expenditure Survey measures how consumers allocate their spending. A recent survey asked respondents to specify the amount of their budget spent on food, housing, transportation, healthcare, and insurance and pensions. Also recorded were the
> The random variable X has the following probability distribution. Find the following probabilities. a. P(X > 0) b. P(X ≥ 1) c. P(X ≥ 2) d. P(2 ≤ X ≤ 5) -3 2 8 P(x) .2 3 .4
> It is recommended that women age 40 and older have a mammogram annually. A recent report indicated that if a woman has annual mammograms over a 10-year period, there is a 60% probability that there will be at least one false-positive result. (A false-pos
> According to a Gallup Poll conducted in 2015 only 1% of Russians approved of U.S. leadership. To evaluate whether this claim has any merit a statistician took a random sample of 100 Russians. Determine the probability of these events. a. No one approved
> When Earth traveled through the storm of meteorites trailing the comet Tempel-Tuttle on November 17, 1998, the storm was 1,000 times as intense as the average meteor storm. Before the comet arrived, telecommunication companies worried about the potential
> An investor hears a radio report that says in 60% of the stocks on the New York Stock Exchange increased in value. He realizes that he owns 20 stocks on the NYSE. Determine the probability of the following events. a. 15 or more stocks increased in value.
> In 1941 Joe DiMaggio hit in 56 consecutive games, a record that is predicted to never be broken. To see how unlikely this streak was, assume that a player batting .350 gets to bat 5 times in a game (with no walks and hit by pitch). a. What is the probabi
> Advertising researchers have developed a theory that states that commercials that appear in violent television shows are less likely to be remembered and will thus be less effective. After examining samples of viewers who watch violent and nonviolent pro
> A pharmaceutical researcher working on a cure for baldness noticed that middle-aged men who are balding at the crown of their head have a 45% probability of suffering a heart attack over the next decade. In a sample of 100 middle-age balding men, what ar
> Researchers at the University of Pennsylvania School of Medicine theorized that children under 2 years old who sleep in rooms with the light on have a 40% probability of becoming myopic by age 16. Suppose that researchers found 25 children who slept with
> According to climatologists, the long-term average for Atlantic storms is 9.6 per season (June 1 to November 30), with 6 becoming hurricanes and 2.3 becoming intense hurricanes. Find the probability of the following events. a. Ten or more Atlantic storms
> Second-year business students at many universities are required to take 10 one-semester courses. The number of courses that result in a grade of A is a discrete random variable. Suppose that each value of this random variable has the same probability. De
> Most Miami Beach restaurants offer “early-bird” specials. These are lower-priced meals that are available only from 4 to 6 p.m. However, not all customers who arrive between 4 and 6 p.m. order the special. In fact, only 70% do. a. Find the probability th
> Shutouts in the National Hockey League occur randomly and independently at a rate of 1 every 20 games. Calculate the probability of the following events. a. 2 shutouts in the next 10 games b. 25 shutouts in 400 games c. A shutout in tonight’s game
> An auditor is preparing for a physical count of inventory as a means of verifying its value. Items counted are reconciled with a list prepared by the storeroom supervisor. In one particular firm, 20% of the items counted cannot be reconciled without revi
> Many cell phone service providers offer family plans wherein parents who subscribe can get discounts for other family members. Suppose that the number of cell phones per family is Poisson distributed with a mean of 1.5. If one family is randomly selected
> University and college students are relatively confident about finding a job after graduation. According to a Gallup survey 50% of students are say now is a good time to find a quality job. Suppose you randomly select 10 students and ask about their futu
> Ten percent of American adults devote so much time to playing video games either on a console, computer, or cell phone that they consider themselves to be “gamers” according to a Pew Research Center report. Suppose that a random sample of 25 American adu
> The Powerball lottery is one of the most popular lotteries in the United States. From time to time, the jackpot exceeds $100 million. As a result so many more people buy Powerball tickets that there are frequent lineups at convenience stores. A statistic
> Has the educational level of adults changed over the past 15 years? To help answer this question the Bureau of Labor Statistics compiled the following table, which lists the number (1,000) of adults 25 years of age and older who are employed. Use a graph
> Lotteries are an important income source for various governments around the world. However, the availability of lotteries and other forms of gambling have created a social problem: gambling addicts. A critic of government-controlled gambling contends tha
> Hikers and other outdoor enthusiasts have a new concern, the Zika virus. Physicians are recommending that people use a mosquito repellant while in areas where mosquitoes are present. A statistician estimated that 80% of hikers would be spraying themselve
> Using historical records, the personnel manager of a plant has determined the probability distribution of X, the number of employees absent per day. It is a. Find the following probabilities. P(2 ≤ X ≤ 5) P(X >
> The number of arrivals at a car wash is Poisson distributed with a mean of eight per hour. a. What is the probability that 10 cars will arrive in the next hour? b. What is the probability that more than 5 cars will arrive in the next hour? c. What is the
> Gallup Organization Date: May 2016 Population: American adults Question: “Please tell me whether you strongly favor or strongly oppose keeping the Affordable Care Act in place. Responses: 1. Favor 2. Oppose 3. No opinion Use a graphical technique to summ
> The final exam in a one-term statistics course is taken in the December exam period. Students who are sick or have other legitimate reasons for missing the exam are allowed to write a deferred exam scheduled for the first week in January. A statistics pr
> An airline boasts that 77.4% of its flights were on time. If we select five flights at random, what is the probability that all five are on time?
> A recent Pew Center Research survey revealed that 15% of American adults have used an online dating service. Suppose a statistician randomly selected 20 American adults. a. What is the probability that exactly 3 used an online dating service? b. What is
> In a Gallup poll 20% of adults said that they had a great deal or quite a lot of confidence in newspapers. If we take a random sample of 25 adults and ask each whether they had a great deal or quite a lot of confidence in newspapers determine probability
> The number of users of an automatic banking machine is Poisson distributed. The mean number of users per 5-minute interval is 1.5. Find the probability of the following events. a. No users in the next 5 minutes b. Five or fewer users in the next 15 minut
> Cars arriving for gasoline at a particular gas station follow a Poisson distribution with a mean of 5 per hour. a. Determine the probability that over the next hour only one car will arrive. b. Compute the probability that in the next 3 hours more than 2
> The number of trucks crossing at the Ambassador Bridge connecting Detroit, Michigan, and Windsor, Ontario, is Poisson distributed with a mean of 1.5 per minute. a. What is the probability that in any 1-minute time span two or more trucks will cross the b
> After conducting a survey of golfers a statistician concludes that the number of lost balls in a round is Poisson distributed with a mean of 2. Find the probability of the following events. a. A golfer loses no golf balls b. A golfer loses 4 or more no g
> In a recent census, the number of color televisions per household was recorded. a. Develop the probability distribution of X, the number of color televisions per household. b. Determine the following probabilities. P(X ≤ 2) P(X >
> The random variable in Exercise 7.44 was the number of holes in one by the members of a private golf course. In fact, the number of holes in one is Poisson distributed with a mean of 1. a. What proportion of members never have had a hole in one? b. What
> At a public library one of the librarians surveys individuals reading online newspapers. After analyzing the data she concludes that the number of newspapers read online is Poisson distributed with a mean of 5. a. What proportion of library patrons read
> The random variable in Exercise 7.30 was the number of stores entered by customers at a mall. Suppose that the random variable is Poisson distributed with a mean of 4. a. What proportion of mall customers enter 5 stores or more? b. Compute the probabilit
> At an auction of antique furniture a statistician kept track of the number of bids for each item. After an analysis of the figures she concludes that the number of bids is Poisson distributed with a mean of 2.5. a. Calculate the probability that on any i
> Flaws in a carpet tend to occur randomly and independently at a rate of one every 200 square feet. What is the probability that a carpet that is 8 feet by 10 feet contains no flaws?
> The number of bank robberies that occur in a large North American city is Poisson distributed with a mean of 1.8 per day. Find the probabilities of the following events. a. Three or more bank robberies in a day. b. Between 10 and 15 (inclusive) robberies
> In older cities across North America, infrastructure is deteriorating, including water lines that supply homes and businesses. A report to the Toronto city council stated that there are on average 30 water line breaks per 100 kilometers per year in the c
> Hits on a personal website occur quite infrequently. They occur randomly and independently with an average of five per week. a. Find the probability that the site gets 10 or more hits in a week. b. Determine the probability that the site gets 20 or more
> The number of students who seek assistance with their statistics assignments is Poisson distributed with a mean of two per day. a. What is the probability that no students seek assistance tomorrow? b. Find the probability that 10 students seek assistance
> Snowfalls occur randomly and independently over the course of winter in a Minnesota city. The average is one snowfall every 3 days. a. What is the probability of five snowfalls in 2 weeks? b. Find the probability of a snowfall today.
> Let X be the random variable designating the number of spots that turn up when a balanced die is rolled. What is the probability distribution of X?
> The number of accidents that occur at a busy intersection is Poisson distributed with a mean of 3.5 per week. Find the probability of the following events. a. No accidents in one week b. Five or more accidents in one week c. One accident today
> Given that X is a Poisson random variable with = .5, use the formula to determine the following probabilities. a. P(X = 0) b. P(X = 1) c. P(X = 2)
> Given a Poisson random variable with = 2, use the formula to find the following probabilities. a. P(X = 0) b. P(X = 3) c. P(X = 5)
> In a recent Gallup poll 53% of American adults believed that Congress is doing a poor or bad job. Suppose that you randomly choose 100 American adults and ask their opinion about Congress. a. Determine the probability that more than half say that Congres
> The statistics practitioner in Exercise 7.116 also determined that if a batter hits a line drive, the probability of an out is 23%. Determine the following probabilities. a. In a game with 10 line drives, at least 5 are outs. b. In a game with 25 line dr
> In a Bon Appetit poll, 38% of people said that chocolate was their favorite flavor of ice cream. A sample of 20 people was asked to name their favorite flavor of ice cream. What is the probability that half or more of them prefer chocolate?
> According to a Gallup Poll 52% of American adults think that protecting the environment should be given priority over developing U.S. energy supplies. Thirty-six percent think that developing energy supplies is more important, and 6% believe the two are
> In the game of roulette, a steel ball is rolled onto a wheel that contains 18 red, 18 black, and 2 green slots. If the ball is rolled 25 times, find the probabilities of the following events. a. The ball falls into the green slots two or more times. b. T
> Researchers have developed statistical models based on financial ratios that predict whether a company will go bankrupt over the next 12 months. In a test of one such model, the model correctly predicted the bankruptcy of 85% of firms that did in fact fa
> The owner of an appliance store is interested in the relationship between the price at which an item is sold (regular or sale price) and the customer’s decision on whether to purchase an extended warranty. After analyzing her records, s
> Determine whether each of the following is a valid probability distribution. a. x 0 1 2 3 P(x) .1 .3 .4 .1 b. x 5 −6 10 0 P(x) .01 .01 .01 .97 c. x 14 12 −7 13 P(x) .25 .46 .04 .24
> In the game of blackjack as played in casinos in Las Vegas, Atlantic City, and Niagara Falls, as well as in many other cities, the dealer has the advantage. Most players do not play very well. As a result, the probability that the average player wins a h