Mathematical Statistics with Applications
7th Edition
ISBN: 9780495110811
Author: Dennis Wackerly, William Mendenhall, Richard L. Scheaffer
Publisher: Cengage Learning
expand_more
expand_more
format_list_bulleted
Concept explainers
Textbook Question
Chapter 4.11, Problem 155E
A builder of houses needs to order some supplies that have a waiting time Y for delivery, with a continuous uniform distribution over the interval from 1 to 4 days. Because she can get by without them for 2 days, the cost of the delay is fixed at $100 for any waiting time up to 2 days. After 2 days, however, the cost of the delay is $100 plus $20 per day (prorated) for each additional day. That is, if the waiting time is 3.5 days, the cost of the delay is $100 + $20(1.5) = $130. Find the expected value of the builder’s cost due to waiting for supplies.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
The starting time of a class is uniformly distributed between 10:00 and 10:05. If a student arrives early and has to wait t minutes for the class to start, then the student incurs a penalty of At, which accounts for the waste in the student's time. On the other hand, if the student arrives t minutes after the class has started, then the student incurs a penalty of A2t, which accounts for the information the student has missed. If the student arrives at x minutes after 10:00, what is the expected penalty incurred by the student? What value of x minimizes the expected penalty?
A company pays its employees an average wage of $22.50 an hour with a standarddeviation of $2.30. If the wages are approximately normally distributed and paid to thenearest centavos, what is the highest 5% of the employees have hourly wages that are greater than whatamount?
Suppose that you enter a fantasy baseball league. Suppose that the 2021 team budget, say , is randomly drawn from a uniform distribution on the interval , where the unit is U.S. million dollars. In addition, suppose that after the value has been observed , the 2022 team budget, say , is randomly drawn from a uniform distribution on the interval . In other words, the 2022 budget is at most as large as the 2021 budget.
a) For any given value of x(50<x<350), obtain E[Y|X=x]
b) In view of part (a), obtain E[Y|X]
c) Atlanta Braves won the 2021 World Series title. Their estimated 2022 payroll is about $130 million. Would your 2022 fantasy baseball budget be on average larger than their 2022 payroll? Explain briefly.
Chapter 4 Solutions
Mathematical Statistics with Applications
Ch. 4.2 - Prob. 1ECh. 4.2 - A box contains five keys, only one of which will...Ch. 4.2 - A Bernoulli random variable is one that assumes...Ch. 4.2 - Let Y be a binomial random variable with n = 1 and...Ch. 4.2 - Suppose that Y is a random variable that takes on...Ch. 4.2 - Consider a random variable with a geometric...Ch. 4.2 - Let Y be a binomial random variable with n=10 and...Ch. 4.2 - Prob. 8ECh. 4.2 - A random variable Y has the following distribution...Ch. 4.2 - Refer to the density function given in Exercise...
Ch. 4.2 - Suppose that Y possesses the density function...Ch. 4.2 - Prob. 12ECh. 4.2 - A supplier of kerosene has a 150-gallon tank that...Ch. 4.2 - A gas station operates two pumps, each of which...Ch. 4.2 - As a measure of intelligence, mice are timed when...Ch. 4.2 - Let Y possess a density function...Ch. 4.2 - Prob. 17ECh. 4.2 - Prob. 18ECh. 4.2 - Prob. 19ECh. 4.3 - Prob. 20ECh. 4.3 - If, as in Exercise 4.17, Y has density function...Ch. 4.3 - Prob. 22ECh. 4.3 - Prob. 23ECh. 4.3 - If Y is a continuous random variable with density...Ch. 4.3 - Prob. 25ECh. 4.3 - If Y is a continuous random variable with mean ...Ch. 4.3 - Prob. 27ECh. 4.3 - Prob. 28ECh. 4.3 - Prob. 29ECh. 4.3 - The proportion of time Y that an industrial robot...Ch. 4.3 - Prob. 31ECh. 4.3 - Weekly CPU time used by an accounting firm has...Ch. 4.3 - The pH of water samples from a specific lake is a...Ch. 4.3 - Prob. 34ECh. 4.3 - If Y is a continuous random variable such that...Ch. 4.3 - Prob. 36ECh. 4.3 - Prob. 37ECh. 4.4 - Suppose that Y has a uniform distribution over the...Ch. 4.4 - If a parachutist lands at a random point on a line...Ch. 4.4 - Suppose that three parachutists operate...Ch. 4.4 - Prob. 41ECh. 4.4 - Prob. 42ECh. 4.4 - A circle of radius r has area A = r2. If a random...Ch. 4.4 - Prob. 44ECh. 4.4 - Upon studying low bids for shipping contracts, a...Ch. 4.4 - 4.45 Upon studying low bids for shipping...Ch. 4.4 - The failure of a circuit board interrupts work...Ch. 4.4 - If a point is randomly located in an interval (a,...Ch. 4.4 - Prob. 49ECh. 4.4 - Prob. 50ECh. 4.4 - The cycle time for trucks hauling concrete to a...Ch. 4.4 - Refer to Exercise 4.51. Find the mean and variance...Ch. 4.4 - Prob. 53ECh. 4.4 - Prob. 54ECh. 4.4 - Refer to Exercise 4.54. Suppose that measurement...Ch. 4.4 - Refer to Example 4.7. Find the conditional...Ch. 4.4 - Prob. 57ECh. 4.5 - Use Table 4, Appendix 3, to find the following...Ch. 4.5 - Prob. 59ECh. 4.5 - Prob. 60ECh. 4.5 - What is the median of a normally distributed...Ch. 4.5 - If Z is a standard normal random variable, what is...Ch. 4.5 - A company that manufactures and bottles apple...Ch. 4.5 - The weekly amount of money spent on maintenance...Ch. 4.5 - In Exercise 4.64, how much should be budgeted for...Ch. 4.5 - A machining operation produces bearings with...Ch. 4.5 - Prob. 67ECh. 4.5 - Prob. 68ECh. 4.5 - Refer to Exercise 4.68. If students possessing a...Ch. 4.5 - Refer to Exercise 4.68. Suppose that three...Ch. 4.5 - Wires manufactured for use in a computer system...Ch. 4.5 - Prob. 72ECh. 4.5 - The width of bolts of fabric is normally...Ch. 4.5 - A soft-drink machine can be regulated so that it...Ch. 4.5 - The machine described in Exercise 4.75 has...Ch. 4.5 - The SAT and ACT college entrance exams are taken...Ch. 4.5 - Show that the maximum value of the normal density...Ch. 4.5 - Show that the normal density with parameters and ...Ch. 4.5 - Assume that Y is normally distributed with mean ...Ch. 4.6 - a If 0, () is defined by ()=0y1eydy, show that...Ch. 4.6 - Use the results obtained in Exercise 4.81 to prove...Ch. 4.6 - The magnitude of earthquakes recorded in a region...Ch. 4.6 - If Y has an exponential distribution and P(Y 2) =...Ch. 4.6 - Refer to Exercise 4.88. Of the next ten...Ch. 4.6 - The operator of a pumping station has observed...Ch. 4.6 - The length of time Y necessary to complete a key...Ch. 4.6 - Historical evidence indicates that times between...Ch. 4.6 - One-hour carbon monoxide concentrations in air...Ch. 4.6 - Prob. 95ECh. 4.6 - Prob. 96ECh. 4.6 - Prob. 97ECh. 4.6 - Consider the plant of Exercise 4.97. How much of...Ch. 4.6 - If 0 and is a positive integer, the...Ch. 4.6 - Prob. 100ECh. 4.6 - Applet Exercise Refer to Exercise 4.88. Suppose...Ch. 4.6 - Prob. 102ECh. 4.6 - Explosive devices used in mining operations...Ch. 4.6 - The lifetime (in hours) Y of an electronic...Ch. 4.6 - Four-week summer rainfall totals in a section of...Ch. 4.6 - The response times on an online computer terminal...Ch. 4.6 - Refer to Exercise 4.106. a. Use Tchebysheffs...Ch. 4.6 - The weekly amount of downtime Y (in hours) for an...Ch. 4.6 - If Y has a probability density function given by...Ch. 4.6 - Suppose that Y has a gamma distribution with...Ch. 4.6 - Prob. 112ECh. 4.7 - Prob. 120ECh. 4.7 - Prob. 122ECh. 4.7 - The relative humidity Y, when measured at a...Ch. 4.7 - The percentage of impurities per batch in a...Ch. 4.7 - Prob. 125ECh. 4.7 - Suppose that a random variable Y has a probability...Ch. 4.7 - Verify that if Y has a beta distribution with = ...Ch. 4.7 - Prob. 128ECh. 4.7 - During an eight-hour shift, the proportion of time...Ch. 4.7 - Prob. 130ECh. 4.7 - Errors in measuring the time of arrival of a wave...Ch. 4.7 - Prob. 132ECh. 4.7 - Prob. 133ECh. 4.7 - Prob. 134ECh. 4.7 - Prob. 135ECh. 4.9 - Suppose that the waiting time for the first...Ch. 4.9 - Prob. 137ECh. 4.9 - Example 4.16 derives the moment-generating...Ch. 4.9 - The moment-generating function of a normally...Ch. 4.9 - Identify the distributions of the random variables...Ch. 4.9 - If 1 2, derive the moment-generating function of...Ch. 4.9 - Refer to Exercises 4.141 and 4.137. Suppose that Y...Ch. 4.9 - The moment-generating function for the gamma...Ch. 4.9 - Consider a random variable Y with density function...Ch. 4.9 - A random variable Y has the density function...Ch. 4.10 - A manufacturer of tires wants to advertise a...Ch. 4.10 - A machine used to fill cereal boxes dispenses, on...Ch. 4.10 - Find P(|Y | 2) for Exercise 4.16. Compare with...Ch. 4.10 - Find P(|Y | 2) for the uniform random variable....Ch. 4.10 - Prob. 150ECh. 4.10 - Prob. 151ECh. 4.10 - Refer to Exercise 4.109. Find an interval that...Ch. 4.10 - Refer to Exercise 4.129. Find an interval for...Ch. 4.11 - A builder of houses needs to order some supplies...Ch. 4.11 - Prob. 157ECh. 4.11 - Consider the nail-firing device of Example 4.15....Ch. 4.11 - Prob. 159ECh. 4 - Prob. 160SECh. 4 - Prob. 161SECh. 4 - Prob. 162SECh. 4 - Prob. 163SECh. 4 - The length of life of oil-drilling bits depends...Ch. 4 - Prob. 165SECh. 4 - Prob. 166SECh. 4 - Prob. 167SECh. 4 - Prob. 168SECh. 4 - An argument similar to that of Exercise 4.168 can...Ch. 4 - Prob. 170SECh. 4 - Suppose that customers arrive at a checkout...Ch. 4 - Prob. 172SECh. 4 - Prob. 173SECh. 4 - Prob. 174SECh. 4 - Prob. 175SECh. 4 - If Y has an exponential distribution with mean ,...Ch. 4 - Prob. 180SECh. 4 - Prob. 181SECh. 4 - Prob. 182SECh. 4 - Prob. 183SECh. 4 - Prob. 184SECh. 4 - Prob. 185SECh. 4 - Prob. 186SECh. 4 - Refer to Exercise 4.186. Resistors used in the...Ch. 4 - Prob. 188SECh. 4 - Prob. 189SECh. 4 - Prob. 190SECh. 4 - Prob. 191SECh. 4 - The velocities of gas particles can be modeled by...Ch. 4 - Because P(YyYc)=F(y)F(c)1F(c) has the properties...Ch. 4 - Prob. 194SECh. 4 - Prob. 195SECh. 4 - Prob. 196SECh. 4 - Prob. 197SECh. 4 - Prob. 198SECh. 4 - Prob. 199SECh. 4 - Prob. 200SE
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, statistics and related others by exploring similar questions and additional content below.Similar questions
- If X1, X2, ... , Xk have the multinomial distribution of Definition 8, show that the mean of the marginal distribu-tion of Xi is nθi for i = 1, 2, ... , k.arrow_forwardYou and two other people are to place bids for an object, with the high bid winning. If you win, you plan to sell the object immediately for 10,000.(a) How much should you bid to maximize your expected profit if you believe that the bids of the others can be regarded as being independent and uniformly distributed between 7,000 and 10,000?arrow_forwardA statistics professor plans classes so carefully that the length of her classes are uniformly distributed between 49.0 and 59.0 minutes. Find the probaility that a given class period runs between 50.75 and 51.5 minutes?arrow_forward
- Suppose that the waiting time for a college campus shuttle is uniformly distributed between 8and 28 minutes. Describe the worst 15% of all waiting times for a college campus shuttle.© less than or equal to 11 minutes© greater than or equal to 25 minutesO less than or equal to 15 minutesgreater than or equal to 15 minutesarrow_forwardAssuming that workers' salaries in your company are uniformly distributed between $10,000 and $40,000 per year. Find the amount of money that 25% of the workers make more than that value?arrow_forwardSuppose an electric-vehicle manufacturing company estimates that a driver who commutes 50 miles per day in a particular vehicle has a recharging time that has a uniformly distributed between 70 and 110 minutes. What is the expected recharging time in minutes?(Enter your answer with no decimal places).arrow_forward
- The amount of time it takes Alice to make dinner is continuous and uniformly distributed between 10 minutes and 46 minutes. What is the probability that it takes Alice more than 42 minutes to finish making dinner given that it has already taken her more than 32 minutes in the making of her dinner?arrow_forwardThe Greer Tire company manufactures a new steel-belted radial tire to be sold through a national chain of discount stores. Because the tire is a new product, Greer’s managers believe that the mileage guarantee offered with the tire will be an important factor in the acceptance of the product. Let X = miles that the tires last: X~N(60,000 2,500) Find the mileage guarantee that ensures this company will repair no more than 15% of its product for free. Assume the distribution of tire mileage is normal.arrow_forwardIn bacterial counts with a haemacytometer, the number of bacteria per quadrat has a Poisson distribution with probability mass function f(x), where f(x) = θ x e −θ/x! and θ is to be estimated. If there are many bacteria in a quadrat, it is difficult to count them all, and so the only information recorded is that the number of bacteria exceeds a certain limit c, a large positive integer. In a random sample of n quadrats, it was.arrow_forward
- You and two other people are to place bids for an object, with the high bid winning. If you win, you plan to sell the object immediately for 10,000.(a) How much should you bid to maximize your expected profit if you believe that the bids of the others can be regarded as being independent and uniformly distributed between 7,000 and 10,000?(b) How much should you bid to maximize your expected profit if you believe that the bids of the others can be regarded as identical and uniformly distributed between 7,000 and 10,000?arrow_forwardA company pays its employees an average wage of $22.50 an hour with a standarddeviation of $2.30. If the wages are approximately normally distributed and paid to thenearest centavos, what percentage of the workers receive wages between $20 and $23.50?arrow_forwardAn insurance company offers its policyholders a number of differentpremium payment options. For a randomly selected policyholder, let X=the number of months between successive payments. The cdf of X is asfollows:(attached) a. What is the pmf of X?b. Using just the cdf, compute P(3≤ x ≤6) and P(4 ≤ X).arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Algebra & Trigonometry with Analytic GeometryAlgebraISBN:9781133382119Author:SwokowskiPublisher:Cengage
Algebra & Trigonometry with Analytic Geometry
Algebra
ISBN:9781133382119
Author:Swokowski
Publisher:Cengage
Continuous Probability Distributions - Basic Introduction; Author: The Organic Chemistry Tutor;https://www.youtube.com/watch?v=QxqxdQ_g2uw;License: Standard YouTube License, CC-BY
Probability Density Function (p.d.f.) Finding k (Part 1) | ExamSolutions; Author: ExamSolutions;https://www.youtube.com/watch?v=RsuS2ehsTDM;License: Standard YouTube License, CC-BY
Find the value of k so that the Function is a Probability Density Function; Author: The Math Sorcerer;https://www.youtube.com/watch?v=QqoCZWrVnbA;License: Standard Youtube License