Concept explainers
Comcast Corporation is the largest cable television company, the second largest Internet service provider, and the fourth largest telephone service provider in the United States. Generally known for quality and reliable service, the company periodically experiences unexpected service interruptions. On January 14, 2014, such an interruption occurred for the Comcast customers living in southwest Florida. When customers called the Comcast office, a recorded message told them that the company was aware of the service outage and that it was anticipated that service would be restored in two hours. Assume that two hours is the mean time to do the repair and that the repair time has an exponential
- a. What is the probability that the cable service will be repaired in one hour or less?
- b. What is the probability that the repair will take between one hour and two hours?
- c. For a customer who calls the Comcast office at 1:00 p.m., what is the probability that the cable service will not be repaired by 5:00 p.m.?
Want to see the full answer?
Check out a sample textbook solutionChapter 6 Solutions
Modern Business Statistics with Microsoft Office Excel (with XLSTAT Education Edition Printed Access Card) (MindTap Course List)
- Kentville, a community of 10,000 people, resides next to a krypton mine, and there is a concern that the emission from the krypton smelter have resulted in adverse effects. Specifically, Kryptonosis seems to have killed 12 of Kentville’s inhabitants last year. A neighboring community, Lanesburg, has 25,000 inhabitants and is far enough from the smelter to not be affected by the emission. In Lanesburg, only three people last year died of Kryptonosis. Given that the number of deaths in Kentville and their causes last year were: Heart attack=7 Accidents=4 Kryptonosis=12 Other=6 What is the risk of dying of Kryptonosis in Kentville relative to non-contaminated locality?What is the risk of dying of Kryptonosis in Kentville relative to deaths due to other causes? How many times the chance of dying of Kryptonosis compared to dying of accidents ? How many times the chance of dying of Kryptonosis compared to Other causes?arrow_forwardThe Conch Café, located in Gulf Shores, Alabama, features casual lunches with a great view of the Gulf of Mexico. To accommodate the increase in business during the summer vacation season, Fuzzy Conch, the owner, hires a large number of servers as seasonal help. When he interviews a prospective server, he would like to provide data on the amount a server can earn in tips. He believes that the amount of the bill and the number of diners are both related to the amount of the tip. He gathered the following sample information. Customer Amount of Tip Amount of Bill Number of Diners Customer Amount of Tip Amount of Bill Number of Diners 1 $ 7.00 $ 48.97 5 16 $ 3.30 $ 23.59 2 2 4.50 28.23 4 17 3.50 22.30 2 3 1.00 10.65 1 18 3.25 32.00 2 4 2.40 19.82 3 19 5.40 50.02 4 5 5.00 28.62 3 20 2.25 17.60 3 6 4.25 24.83 2 21 5.50 44.47 4 7 0.50 6.24 1 22 3.00 20.27 2…arrow_forwardThe Conch Café, located in Gulf Shores, Alabama, features casual lunches with a great view of the Gulf of Mexico. To accommodate the increase in business during the summer vacation season, Fuzzy Conch, the owner, hires a large number of servers as seasonal help. When he interviews a prospective server, he would like to provide data on the amount a server can earn in tips. He believes that the amount of the bill and the number of diners are both related to the amount of the tip. He gathered the following sample information. Customer Amount of Tip Amount of Bill Number of Diners Customer Amount of Tip Amount of Bill Number of Diners 1 $ 6.05 $ 73.22 1 16 $ 3.30 $ 23.59 2 2 4.50 28.23 4 17 3.50 22.30 2 3 1.00 10.65 1 18 3.25 32.00 2 4 2.40 19.82 3 19 5.40 50.02 4 5 5.00 28.62 3 20 2.25 17.60 3 6 4.25 24.83 2 21 1.40 41.80 5 7 .50 6.25 1 22 3.00 20.27 2…arrow_forward
- Arianna Estefan manages Salmon Falls Park, which has two flagship roller coasters, the Flyer and the Destroyer. When Arianna walks around the park during hours of operation, she notices that there are fewer people waiting in line for the Flyer than for the Destroyer. Since both roller coasters have similar capacities and similar run times, both roller coasters should have about the same number of riders. Based on the anecdotal evidence, Arianna claims that the population mean number of riders per hour on the Flyer is less than the population mean number of riders per hour on the Destroyer. Arianna reviews data collected in the past and assumes that the population standard deviation is 48.29 for the Flyer and 51.86 for the Destroyer. Arianna randomly selects hours during which the attendant of each ride counts the number of riders. The sampling occurs over the course of several weeks. The results are provided in the table shown below. Assuming the conditions needed for the hypothesis…arrow_forwardArianna Estefan manages Salmon Falls Park, which has two flagship roller coasters, the Flyer and the Destroyer. When Arianna walks around the park during hours of operation, she notices that there are fewer people waiting in line for the Flyer than for the Destroyer. Since both roller coasters have similar capacities and similar run times, both roller coasters should have about the same number of riders. Based on the anecdotal evidence, Arianna claims that the population mean number of riders per hour on the Flyer is less than the population mean number of riders per hour on the Destroyer. Arianna reviews data collected in the past and assumes that the population standard deviation is 48.29 for the Flyer and 51.86 for the Destroyer. Arianna randomly selects hours during which the attendant of each ride counts the number of riders. The sampling occurs over the course of several weeks. The results are provided in the table shown below. Assuming the conditions needed for the hypothesis…arrow_forwardIn February 2021, the Chicago Tribune reported:“The overdose epidemic that has ravaged Chicago has not spared the nearby suburbs, some of which have death rates comparable to anything seen in the city, according to a report released this week by the Cook County Department of Public Health. ZIP codes in the towns of Worth, Broadview, Maywood, and Forest Park, areas that “have substantially lower median household incomes and higher poverty rates,” have been especially hard-hit, the report said.”In the article, they claimed that lower incomes were associated with higher overdose death rates and that overdose death rates are increasing over time. The data you have been analyzing wasn’t focused on Chicago, obviously. But do your results support the general gist of the statistical argument being made in this Tribune excerpt? Please address:• Do overdose death rates appear to be associated with per capita income (use scatterplot)?• Do overdose death rates appear to be increasing over time…arrow_forward
- According to the American Red Cross, O positive is the most common blood type. Approximately 45% of the U.S. population has type O blood. However, type O is routinely in short supply and in high demand by hospitals—both because it is the most common blood type and because type O negative blood, in particular, is the universal blood type needed for emergency transfusions. The local American Red Cross is holding a blood drive. How many donors should they expect to collect from until they get a donor with type O blood? What is the probability that the first donor with type O blood occurs on the mean of the distribution? Round your answer to the nearest hundredth if necessary. The American Red Cross had 75 donors show up to their drive and donate blood. How many donors would you expect to have type O blood? The American Red Cross had 75 donors show up to their drive and donate blood. By about how many donors would the expected value for donors with type O blood vary? You find out…arrow_forwardDes P. Rada is a third-year business student. In her desire to find her “Mr. Right”, she accessed a Filipino dating site Kindling. To join Kindling, she was required to reveal her private information such as complete name, location, contact details, the school she went to, the companies or places she worked for, etc. These data will eventually be shared by Kindling users, users’ friends or the dating website itself. For whatever reasons, Des P. Rada’s personal data were publicly posted and, hence, made known to others who are not members of Kindling. As a result, Des P. Rada has not only been cyber-bullied by suitors that she disliked and rejected, but ridiculed by some of her classmates, and even stalked by ex-boyfriend Kanor. Des P. Rada blames Kindling of what had happened. Did Kindling violate her rights under the Data Privacy Act? Support your answer with the provision/s of the lawarrow_forwardRecent research commissioned by Vodafone suggests that older workers are the happiest employees (BBC News, July 21, 2008). The report documents that 70% of older workers in England feel fulfilled, compared with just 50% of younger workers. A demographer believes that an identical pattern does not exist in Asia. A survey of 120 older workers in Asia finds that 75 feel fulfilled. A similar survey finds that 58% of 210 younger workers feel fulfilled. (You may find it useful to reference the appropriate table: z table or t table) At the 5% level of significance, test if older workers in Asia feel less fulfilled than their British counterparts. a-1. Select the null and the alternative hypotheses. multiple choice 1 H0: p = 0.70; HA: p ≠ 0.70 H0: p ≤ 0.70; HA: p > 0.70 H0: p ≥ 0.70; HA: p < 0.70 a-2. Calculate the sample proportion. (Round your answer to 3 decimal places.) a-3. Calculate the value of test statistic. (Negative value should be indicated…arrow_forward
- The National Center for Health Statistics, housed within the U.S. Centers for Disease Control and Prevention (CDC), tracks the number of adults in the United States who have health insurance. According to this agency, the uninsured rates for Americans in 2018 are as follows: 5.1% of those under the age of 18, 12.4% of those ages 18-64, and 1.1% of those 65and older do not have health insurance (CDC website). Approximately 22.8% of Americans are under age 18, and 61.4% of Americans are aged 18-64. Given that the person is an uninsured American, what is the probability that the person is 65 or older (to 3 decimals)?arrow_forwardJensen Tire & Auto is in the process of deciding whether to purchase a maintenance contract for its new computer wheel alignment and balancing machine. Managers feel that maintenance expense should be related to usage, and they collected the following information on weekly usage (hours) and annual maintenance expense (in hundreds of dollars).arrow_forwardA statistics instructor would like to know whether it is worthwhile to require students to do weekly homework assignments. For Section1 of the course, homework is assigned, collected and graded each week. In Section2, students are not required to turn in homework. At the end of the semester, the students are given the same final exam. In Section1, the numbers of students getting each grade are: 16 students got A, 22 students got B, 8 students got C, and 4 students got D. In Section2, the numbers of students getting each grade are: 8 students got A, 18 students got B, 18 students got C, and 6 students got D. Is there an association between assigning homework and exam grade? Test at the alpha = 0.05 level. a. We reject the null hypothesis with two-tailed critical values; there is an association between assigning homework and exam grade. b. We reject the null hypothesis with one-tailed critical value; there is an association between assigning homework and exam…arrow_forward
- MATLAB: An Introduction with ApplicationsStatisticsISBN:9781119256830Author:Amos GilatPublisher:John Wiley & Sons IncProbability and Statistics for Engineering and th...StatisticsISBN:9781305251809Author:Jay L. DevorePublisher:Cengage LearningStatistics for The Behavioral Sciences (MindTap C...StatisticsISBN:9781305504912Author:Frederick J Gravetter, Larry B. WallnauPublisher:Cengage Learning
- Elementary Statistics: Picturing the World (7th E...StatisticsISBN:9780134683416Author:Ron Larson, Betsy FarberPublisher:PEARSONThe Basic Practice of StatisticsStatisticsISBN:9781319042578Author:David S. Moore, William I. Notz, Michael A. FlignerPublisher:W. H. FreemanIntroduction to the Practice of StatisticsStatisticsISBN:9781319013387Author:David S. Moore, George P. McCabe, Bruce A. CraigPublisher:W. H. Freeman