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 157E
Refer to Exercise 3.156.
- a If W = 3Y, use the moment-generating
function of W to show that E(W) = 3E(Y) and V(W) = 9V(Y). - b If X = Y – 2, use the moment-generating function of X to show that E(X) = E(Y) – 2 and V(X) = V(Y).
3.156 Suppose that Y is a random variable with moment-generating function m(t).
- a What is m(0)?
- b If W = 3Y, show that the moment-generating function of W is m(3t).
- c If X = Y –2, show that the moment-generating function of X is e–2tm(t).
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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. 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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. 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