Elementary Statistics (Text Only)
2nd Edition
ISBN: 9780077836351
Author: Author
Publisher: McGraw Hill
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Chapter 10.2, Problem 17E
Defective electronics: A team of designers was given the task of reducing the defect rate in the manufacture of a certain printed circuit board. The team decided to reconfigure the cooling system. A total of 973 boards produced the week before the reconfiguration was implemented, and 254 of these were defective. A total of 847 boards were produced the week after reconfiguration, and 95 of these were defective.
- Construct a 90% confidence inters-al for the decrease in the defective rate after the reconfiguration.
- A quality control engineer claims that the reconfiguration has decreased the proportion of defective parts by more than 0.15. Does the confidence interval contradict this claim?
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Chapter 10 Solutions
Elementary Statistics (Text Only)
Ch. 10.1 - In Exercises 5 and 6, fill in each blank with e...Ch. 10.1 - In Exercises 5 and 6, fill in each blank with e...Ch. 10.1 - Prob. 7ECh. 10.1 - Prob. 8ECh. 10.1 - In Exercises 9-14, construct the confidence...Ch. 10.1 - Prob. 10ECh. 10.1 - In Exercises 9-14, construct the confidence...Ch. 10.1 - Prob. 12ECh. 10.1 - Prob. 13ECh. 10.1 - Prob. 14E
Ch. 10.1 - Does this diet help? A group of 78 people enrolled...Ch. 10.1 - Contaminated water: The concentration of benzene...Ch. 10.1 - Fertilizer: In an agricultural experiment, the...Ch. 10.1 - Computer crashes: A computer system administrator...Ch. 10.1 - Are you smarter than your older brother? In a...Ch. 10.1 - Effectiveness of distance learning: A study was...Ch. 10.1 - Boys and girls: The National Health Statistics...Ch. 10.1 - Body mass index: In a survey of adults with...Ch. 10.1 - Energy drinks: A survey of college students...Ch. 10.1 - Low-fat or low-carb? Are low-fat diets or low-carb...Ch. 10.1 - Online testing: Do you prefer taking tests on...Ch. 10.1 - Drive safely: How often does the average driver...Ch. 10.1 - Interpret calculator display: The following TI-84...Ch. 10.1 - Prob. 28ECh. 10.1 - Prob. 29ECh. 10.1 - Prob. 30ECh. 10.1 - Prob. 31ECh. 10.2 - In Exercises 3 and 4, fill in each blank with the...Ch. 10.2 - Prob. 4ECh. 10.2 - Prob. 5ECh. 10.2 - Prob. 6ECh. 10.2 - In Exercises 7-12, construct the confidence...Ch. 10.2 - In Exercises 7-12, construct the confidence...Ch. 10.2 - In Exercises 7-12, construct the confidence...Ch. 10.2 - In Exercises 7-12, construct the confidence...Ch. 10.2 - In Exercises 7-12, construct the confidence...Ch. 10.2 - Prob. 12ECh. 10.2 - Traffic accidents: Traffic engineers compared...Ch. 10.2 - Computers in the classroom: In a new experimental...Ch. 10.2 - Pain after surgery: In a random sample of 50...Ch. 10.2 - Pretzels: In order to judge the effectiveness of...Ch. 10.2 - Defective electronics: A team of designers was...Ch. 10.2 - Prob. 18ECh. 10.2 - Cancer prevention: Colonoscopy is a medical...Ch. 10.2 - Social media: A Pew poll found that in a sample of...Ch. 10.2 - Interpret calculator display: The following TI-84...Ch. 10.2 - Prob. 22ECh. 10.2 - Prob. 23ECh. 10.2 - Prob. 24ECh. 10.2 - Finding the sample size: Polls are to be conducted...Ch. 10.3 - In Exercises 3 and 4, fill in each blank with the...Ch. 10.3 - Prob. 4ECh. 10.3 - Prob. 5ECh. 10.3 - In Exercises 5 and 6, determine whether the...Ch. 10.3 - Fast computer: microprocessors are compared on a...Ch. 10.3 - Brake wear: For a sample of 9 automobiles, the...Ch. 10.3 - Strength of concrete: The compressive strength, m...Ch. 10.3 - Truck pollution: In an experiment to determine the...Ch. 10.3 - High cholesterol: A group of eight individuals...Ch. 10.3 - Tires and fuel economy: A tire manufacturer is...Ch. 10.3 - Prob. 13ECh. 10.3 - Prob. 14ECh. 10.3 - Interpret calculator display: The following TI-84...Ch. 10.3 - Interpret calculator display: The following TI-84...Ch. 10.3 - Prob. 17ECh. 10.3 - Prob. 18ECh. 10.3 - Advantage of matched pairs: Refer to Exercise 12....Ch. 10.3 - Paired or independent? To construct a confidence...Ch. 10 - In Exercises 1 and 2, determine whether the...Ch. 10 - Prob. 2CQCh. 10 - Prob. 3CQCh. 10 - Prob. 4CQCh. 10 - Prob. 5CQCh. 10 - Prob. 6CQCh. 10 - Prob. 7CQCh. 10 - Prob. 8CQCh. 10 - Prob. 9CQCh. 10 - Prob. 10CQCh. 10 - Prob. 11CQCh. 10 - Refer to Exercise 11. Find the critical value for...Ch. 10 - Prob. 13CQCh. 10 - Prob. 14CQCh. 10 - Prob. 15CQCh. 10 - Prob. 1RECh. 10 - Prob. 2RECh. 10 - Prob. 3RECh. 10 - Prob. 4RECh. 10 - Prob. 5RECh. 10 - Prob. 6RECh. 10 - Prob. 7RECh. 10 - Prob. 8RECh. 10 - Prob. 9RECh. 10 - Prob. 10RECh. 10 - Prob. 11RECh. 10 - Prob. 12RECh. 10 - Prob. 13RECh. 10 - Prob. 14RECh. 10 - Prob. 15RECh. 10 - Prob. 1WAICh. 10 - Prob. 2WAICh. 10 - Prob. 3WAICh. 10 - Prob. 4WAICh. 10 - Prob. 1CSCh. 10 - Prob. 2CSCh. 10 - Prob. 3CS
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