Mathematical Statistics with Applications
7th Edition
ISBN: 9780495110811
Author: Dennis Wackerly, William Mendenhall, Richard L. Scheaffer
Publisher: Cengage Learning
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Textbook Question
Chapter 3.9, Problem 151E
Refer to Exercise 3.145. If Y has moment-generating
3.145 If Y has a geometric distribution with n trials and
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Chapter 3 Solutions
Mathematical Statistics with Applications
Ch. 3.2 - When the health department tested private wells in...Ch. 3.2 - You and a friend play a game where you each toss a...Ch. 3.2 - A group of four components is known to contain two...Ch. 3.2 - Consider a system of water flowing through valves...Ch. 3.2 - A problem in a test given to small children asks...Ch. 3.2 - Five balls, numbered 1, 2, 3, 4, and 5, are placed...Ch. 3.2 - Each of three balls are randomly placed into one...Ch. 3.2 - A single cell can either die, with probability .1,...Ch. 3.2 - In order to verify the accuracy of their financial...Ch. 3.2 - A rental agency, which leases heavy equipment by...
Ch. 3.2 - Persons entering a blood bank are such that 1 in 3...Ch. 3.3 - Let Y be a random variable with p(y) given in the...Ch. 3.3 - Refer to the coin-tossing game in Exercise 3.2....Ch. 3.3 - The maximum patent life for a new drug is 17...Ch. 3.3 - Who is the king of late night TV? An Internet...Ch. 3.3 - Prob. 16ECh. 3.3 - Refer to Exercise 3.7. Find the mean and standard...Ch. 3.3 - Refer to Exercise 3.8. What is the mean number of...Ch. 3.3 - An insurance company issues a one-year 1000...Ch. 3.3 - A manufacturing company ships its product in two...Ch. 3.3 - The number N of residential homes that a fire...Ch. 3.3 - A single fair die is tossed once. Let Y be the...Ch. 3.3 - In a gambling game a person draws a single card...Ch. 3.3 - Approximately 10% of the glass bottles coming off...Ch. 3.3 - Two construction contracts are to be randomly...Ch. 3.3 - A heavy-equipment salesperson can contact either...Ch. 3.3 - A potential customer for an 85,000 fire insurance...Ch. 3.3 - Refer to Exercise 3.3. If the cost of testing a...Ch. 3.3 - If Y is a discrete random variable that assigns...Ch. 3.3 - Suppose that Y is a discrete random variable with...Ch. 3.3 - Suppose that Y is a discrete random variable with...Ch. 3.3 - Suppose that Y is a discrete random variable with...Ch. 3.3 - Let Y be a discrete random variable with mean and...Ch. 3.3 - The manager of a stockroom in a factory has...Ch. 3.4 - Consider the population of voters described in...Ch. 3.4 - a. A meteorologist in Denver recorded Y = the...Ch. 3.4 - In 2003, the average combined SAT score (math and...Ch. 3.4 - The manufacturer of a low-calorie dairy drink...Ch. 3.4 - A complex electronic system is built with a...Ch. 3.4 - The probability that a patient recovers from a...Ch. 3.4 - A multiple-choice examination has 15 questions,...Ch. 3.4 - Refer to Exercise 3.41. What is the probability...Ch. 3.4 - Many utility companies promote energy conservation...Ch. 3.4 - Prob. 44ECh. 3.4 - A fire-detection device utilizes three...Ch. 3.4 - Prob. 46ECh. 3.4 - Use Table 1, Appendix 3, to construct a...Ch. 3.4 - A missile protection system consists of n radar...Ch. 3.4 - A manufacturer of floor wax has developed two new...Ch. 3.4 - In Exercise 2.151, you considered a model for the...Ch. 3.4 - In the 18th century, the Chevalier de Mere asked...Ch. 3.4 - Prob. 52ECh. 3.4 - Tay-Sachs disease is a genetic disorder that is...Ch. 3.4 - Suppose that Y is a binomial random variable based...Ch. 3.4 - Suppose that Y is a binomial random variable with...Ch. 3.4 - An oil exploration firm is formed with enough...Ch. 3.4 - Refer to Exercise 3.56. Suppose the firm has a...Ch. 3.4 - A particular sale involves four items randomly...Ch. 3.4 - Ten motors are packaged for sale in a certain...Ch. 3.4 - A particular concentration of a chemical found in...Ch. 3.4 - Of the volunteers donating blood in a clinic, 80%...Ch. 3.4 - Prob. 62ECh. 3.4 - Consider the binomial distribution with n trials...Ch. 3.4 - Prob. 64ECh. 3.4 - Prob. 65ECh. 3.5 - Suppose that Y is a random variable with a...Ch. 3.5 - Suppose that 30% of the applicants for a certain...Ch. 3.5 - Refer to Exercise 3.67. What is the expected...Ch. 3.5 - About six months into George W. Bushs second term...Ch. 3.5 - An oil prospector will drill a succession of holes...Ch. 3.5 - Prob. 71ECh. 3.5 - Prob. 72ECh. 3.5 - A certified public accountant (CPA) has found that...Ch. 3.5 - Refer to Exercise 3.73. What are the mean and...Ch. 3.5 - The probability of a customer arrival at a grocery...Ch. 3.5 - Prob. 76ECh. 3.5 - If Y has a geometric distribution with success...Ch. 3.5 - Of a population of consumers, 60% are reputed to...Ch. 3.5 - In responding to a survey question on a sensitive...Ch. 3.5 - Two people took turns tossing a fair die until one...Ch. 3.5 - How many times would you expect to toss a balanced...Ch. 3.5 - Refer to Exercise 3.70. The prospector drills...Ch. 3.5 - The secretary in Exercises 2.121 and 3.16 was...Ch. 3.5 - Refer to Exercise 3.83. Find the mean and the...Ch. 3.5 - Find E[Y(Y 1)] for a geometric random variable Y...Ch. 3.5 - Prob. 86ECh. 3.5 - Prob. 87ECh. 3.5 - If Y is a geometric random variable, define Y = Y ...Ch. 3.5 - Prob. 89ECh. 3.6 - The employees of a firm that manufactures...Ch. 3.6 - Refer to Exercise 3.90. If each test costs 20,...Ch. 3.6 - Ten percent of the engines manufactured on an...Ch. 3.6 - Refer to Exercise 3.92. What is the probability...Ch. 3.6 - Refer to Exercise 3.92. Find the mean and variance...Ch. 3.6 - Refer to Exercise 3.92. Given that the first two...Ch. 3.6 - The telephone lines serving an airline reservation...Ch. 3.6 - A geological study indicates that an exploratory...Ch. 3.6 - Prob. 98ECh. 3.6 - In a sequence of independent identical trials with...Ch. 3.6 - If Y is a negative binomial random variable,...Ch. 3.6 - Prob. 101ECh. 3.7 - An urn contains ten marbles, of which five are...Ch. 3.7 - A warehouse contains ten printing machines, four...Ch. 3.7 - Twenty identical looking packets of white power...Ch. 3.7 - In southern California, a growing number of...Ch. 3.7 - Refer to Exercise 3.103. The company repairs the...Ch. 3.7 - A group of six software packages available to...Ch. 3.7 - A shipment of 20 cameras includes 3 that are...Ch. 3.7 - Seed are often treated with fungicides to protect...Ch. 3.7 - A corporation is sampling without replacement for...Ch. 3.7 - Prob. 111ECh. 3.7 - Used photocopy machines are returned to the...Ch. 3.7 - A jury of 6 persons was selected from a group of...Ch. 3.7 - Refer to Exercise 3.113. If the selection process...Ch. 3.7 - Suppose that a radio contains six transistors, two...Ch. 3.7 - In an assembly-line production of industrial...Ch. 3.7 - Five cards are dealt at random and without...Ch. 3.7 - Cards are dealt at random and without replacement...Ch. 3.8 - Let Y denote a random variable that has a Poisson...Ch. 3.8 - Customers arrive at a checkout counter in a...Ch. 3.8 - The random variable Y has a Poisson distribution...Ch. 3.8 - Approximately 4% of silicon wafers produced by a...Ch. 3.8 - Refer to Exercise 3.122. If it takes approximately...Ch. 3.8 - Refer to Exercise 3.122. Assume that arrivals...Ch. 3.8 - The number of typing errors made by a typist has a...Ch. 3.8 - Cars arrive at a toll both according to a Poisson...Ch. 3.8 - Refer to Exercise 3.128. How long can the...Ch. 3.8 - A parking lot has two entrances. Cars arrive at...Ch. 3.8 - The number of knots in a particular type of wood...Ch. 3.8 - The mean number of automobiles entering a mountain...Ch. 3.8 - Assume that the tunnel in Exercise 3.132 is...Ch. 3.8 - Consider a binomial experiment for n = 20, p =...Ch. 3.8 - A salesperson has found that the probability of a...Ch. 3.8 - Increased research and discussion have focused on...Ch. 3.8 - The probability that a mouse inoculated with a...Ch. 3.8 - Let Y have a Poisson distribution with mean . Find...Ch. 3.8 - In the daily production of a certain kind of rope,...Ch. 3.8 - Prob. 140ECh. 3.8 - A food manufacturer uses an extruder (a machine...Ch. 3.8 - Prob. 142ECh. 3.8 - Refer to Exercise 3.142 (c). If the number of...Ch. 3.8 - Prob. 144ECh. 3.9 - Prob. 145ECh. 3.9 - Differentiate the moment-generating function in...Ch. 3.9 - Prob. 147ECh. 3.9 - Prob. 148ECh. 3.9 - Refer to Exercise 3.145. Use the uniqueness of...Ch. 3.9 - Refer to Exercise 3.147. Use the uniqueness of...Ch. 3.9 - Refer to Exercise 3.145. If Y has...Ch. 3.9 - Prob. 152ECh. 3.9 - Find the distributions of the random variables...Ch. 3.9 - Refer to Exercise 3.153. By inspection, give the...Ch. 3.9 - Let m(t)=(1/6)et+(2/6)e2t+(3/6)e3t. Find the...Ch. 3.9 - Suppose that Y is a random variable with...Ch. 3.9 - Refer to Exercise 3.156. a If W = 3Y, use the...Ch. 3.9 - Prob. 158ECh. 3.9 - Prob. 159ECh. 3.9 - Suppose that Y is a binomial random variable based...Ch. 3.9 - Prob. 161ECh. 3.9 - Prob. 162ECh. 3.9 - Prob. 163ECh. 3.10 - Prob. 164ECh. 3.10 - Prob. 165ECh. 3.10 - Prob. 166ECh. 3.11 - Let Y be a random variable with mean 11 and...Ch. 3.11 - Would you rather take a multiple-choice test or a...Ch. 3.11 - This exercise demonstrates that, in general, the...Ch. 3.11 - Prob. 170ECh. 3.11 - Prob. 171ECh. 3.11 - Prob. 172ECh. 3.11 - A balanced coin is tossed three times. Let Y equal...Ch. 3.11 - Prob. 174ECh. 3.11 - Prob. 175ECh. 3.11 - Prob. 176ECh. 3.11 - For a certain section of a pine forest, the number...Ch. 3.11 - Prob. 178ECh. 3.11 - Refer to Exercise 3.91. In this exercise, we...Ch. 3 - Prob. 180SECh. 3 - Prob. 181SECh. 3 - Prob. 182SECh. 3 - Prob. 183SECh. 3 - A city commissioner claims that 80% of the people...Ch. 3 - Prob. 185SECh. 3 - Refer to Exercises 3.67 and 3.68. Let Y denote the...Ch. 3 - Consider the following game: A player throws a...Ch. 3 - Prob. 188SECh. 3 - Prob. 189SECh. 3 - Toss a balanced die and let Y be the number of...Ch. 3 - Two assembly lines I and II have the same rate of...Ch. 3 - Prob. 194SECh. 3 - The number of imperfections in the weave of a...Ch. 3 - Refer to Exercise 3.195. The cost of repairing the...Ch. 3 - The number of bacteria colonies of a certain type...Ch. 3 - Prob. 198SECh. 3 - Insulin-dependent diabetes (IDD) is a common...Ch. 3 - Prob. 200SECh. 3 - Prob. 201SECh. 3 - The number of cars driving past a parking area in...Ch. 3 - Prob. 203SECh. 3 - The probability that any single driver will turn...Ch. 3 - An experiment consists of tossing a fair die until...Ch. 3 - Accident records collected by an automobile...Ch. 3 - Prob. 207SECh. 3 - Prob. 208SECh. 3 - Prob. 209SECh. 3 - Prob. 210SECh. 3 - A merchant stocks a certain perishable item. She...Ch. 3 - Prob. 212SECh. 3 - A lot of N = 100 industrial products contains...Ch. 3 - For simplicity, let us assume that there are two...Ch. 3 - Prob. 216SECh. 3 - Prob. 217SECh. 3 - Prob. 218SE
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