Statistics for Engineers and Scientists
4th Edition
ISBN: 9780073530789
Author: Navidi
Publisher: MCG
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Textbook Question
Chapter 2.6, Problem 29E
Let X and Y be jointly distributed random variables. This exercise leads you through a proof of the fact that –1 ≤ ρX, Y < 1.
- a. Express the quantity V(X – (σX/σY)Y) in terms of σX, σY, and Cov(X, Y).
- b. Use the fact that V(X – (σX/σY)Y) ≥ 0 and Cov(X, Y) = ρX,YσXσY to show that ρX,Y ≤ 1.
- c. Repeat parts (a) and (b) using V(X + (σX/σY)Y) to show that ρX,Y ≥ –1.
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Chapter 2 Solutions
Statistics for Engineers and Scientists
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Ch. 2.1 - A quality-control engineer samples 100 items...Ch. 2.1 - Let V be the event that a computer contains a...Ch. 2.1 - Let S be the event that a randomly selected...Ch. 2.1 - Six hundred paving stones were examined for...Ch. 2.1 - All the fourth-graders in a certain elementary...Ch. 2.1 - A system contains two components, A and B. The...Ch. 2.1 - A system contains two components, A and B. The...Ch. 2.1 - Human blood may contain either or both of two...Ch. 2.1 - True or false: If A and B are mutually exclusive,...Ch. 2.1 - A flywheel is attached to a crankshaft by 12...Ch. 2.2 - DNA molecules consist of chemically linked...Ch. 2.2 - A metallurgist is designing an experiment to...Ch. 2.2 - The article Improved Bioequivalence Assessment of...Ch. 2.2 - A group of 18 people have gotten together to play...Ch. 2.2 - In horse racing, one can make a trifecta bet by...Ch. 2.2 - A college math department consisting of 10 faculty...Ch. 2.2 - A test consists of 15 questions. 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Let Y be the number of chips...Ch. 2.4 - Three components are randomly sampled, one at a...Ch. 2.4 - Resistors labeled 100 have true resistances that...Ch. 2.4 - Elongation (in percent) of steel plates treated...Ch. 2.4 - The lifetime in months of a transistor in a...Ch. 2.4 - A process that manufactures piston rings produces...Ch. 2.4 - Refer to Exercise 16. A competing process produces...Ch. 2.4 - The lifetime, in years, of a certain type of pump...Ch. 2.4 - The level of impurity (in percent) in the product...Ch. 2.4 - The main bearing clearance (in mm) in a certain...Ch. 2.4 - The error in the length of a part (absolute value...Ch. 2.4 - Prob. 22ECh. 2.4 - The thickness of a washer (in mm) is a random...Ch. 2.4 - Particles are a major component of air pollution...Ch. 2.4 - The repair time (in hours) for a certain machine...Ch. 2.4 - The diameter of a rivet (in mm) is a random...Ch. 2.5 - Prob. 1ECh. 2.5 - The bottom of a cylindrical container has an area...Ch. 2.5 - The lifetime of a certain transistor in a certain...Ch. 2.5 - Two batteries, with voltages V1 and V2, are...Ch. 2.5 - A laminated item is composed of five layers. The...Ch. 2.5 - Two independent measurements are made of the...Ch. 2.5 - The molarity of a solute in solution is defined to...Ch. 2.5 - A machine that fills bottles with a beverage has a...Ch. 2.5 - The four sides of a picture frame consist of two...Ch. 2.5 - A gas station earns 2.60 in revenue for each...Ch. 2.5 - A certain commercial jet plane uses a mean of 0.15...Ch. 2.5 - Prob. 12ECh. 2.5 - In the article An Investigation of the...Ch. 2.5 - Prob. 14ECh. 2.5 - Prob. 15ECh. 2.5 - The thickness X of a wooden shim (in mm) has...Ch. 2.5 - Prob. 17ECh. 2.5 - Prob. 18ECh. 2.6 - In a certain community, levels of air pollution...Ch. 2.6 - Prob. 2ECh. 2.6 - Refer to Exercise 1. a. Find the conditional...Ch. 2.6 - Prob. 4ECh. 2.6 - Refer to Exercise 4. The total number of...Ch. 2.6 - Refer to Exercise 4. a. Find the conditional...Ch. 2.6 - Refer to Exercise 4. Assume that the cost of...Ch. 2.6 - The number of customers in line at a supermarket...Ch. 2.6 - Prob. 9ECh. 2.6 - Refer to Exercise 9. a. Find the mean of the total...Ch. 2.6 - Refer to Exercise 9. a. Find the conditional...Ch. 2.6 - Prob. 12ECh. 2.6 - Refer to Exercise 12. Let Z = X + Y represent the...Ch. 2.6 - Refer to Exercise 12. 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What...Ch. 2 - Silicon wafers are used in the manufacture of...Ch. 2 - Two production lines are used to pack sugar into 5...Ch. 2 - Prob. 5SECh. 2 - In a certain type of automobile engine, the...Ch. 2 - An electronic message consists of a string of bits...Ch. 2 - The reading given by a thermometer calibrated in...Ch. 2 - Two dice are rolled. Given that two different...Ch. 2 - In a lot of 10 components, 2 are sampled at random...Ch. 2 - Prob. 11SECh. 2 - Prob. 12SECh. 2 - A snowboard manufacturer has three plants, one in...Ch. 2 - The article Traps in Mineral ValuationsProceed...Ch. 2 - Six new graduates are hired by an engineering...Ch. 2 - Prob. 16SECh. 2 - Let X and Y be independent random variables with x...Ch. 2 - Prob. 18SECh. 2 - Prob. 19SECh. 2 - Prob. 20SECh. 2 - Prob. 21SECh. 2 - A certain plant runs three shifts per day. Of all...Ch. 2 - Prob. 23SECh. 2 - Prob. 24SECh. 2 - Prob. 25SECh. 2 - A stock solution of hydrochloric acid (HC1)...Ch. 2 - Prob. 27SECh. 2 - Prob. 28SECh. 2 - A penny and a nickel are tossed. The penny has...Ch. 2 - Prob. 30SECh. 2 - Prob. 31SECh. 2 - Prob. 32SECh. 2 - Prob. 33SECh. 2 - Prob. 34SECh. 2 - Blood is taken from each of n individuals to be...
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