Intro Stats, Books a la Carte Edition (5th Edition)
5th Edition
ISBN: 9780134210285
Author: Richard D. De Veaux, Paul Velleman, David E. Bock
Publisher: PEARSON
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Textbook Question
Chapter 14, Problem 51E
Pregnancy Assume that the duration of human pregnancies can be described by a Normal model with
- a) What percentage of pregnancies should last between 270 and 280 days?
- b) At least how many days should the longest 25% of all pregnancies last?
- c) Suppose a certain obstetrician is currently providing prenatal care to 60 pregnant women. Let y represent the mean length of their pregnancies. According to the Central Limit Theorem, what’s the distribution of this sample mean, y? Specify the model, mean, and standard deviation.
- d) What’s the
probability that the mean duration of these patients’ pregnancies will be less than 260 days?
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Chapter 14 Solutions
Intro Stats, Books a la Carte Edition (5th Edition)
Ch. 14.2 - Every 10 years, the United States takes a census....Ch. 14.2 - Prob. 2JCCh. 14.2 - Prob. 3JCCh. 14.2 - Every 10 years, the United States takes a census....Ch. 14.2 - Prob. 5JCCh. 14.3 - Prob. 6JCCh. 14 - Salmon A specialty food company sells whole King...Ch. 14 - LSAT The LSAT (a test taken for law school...Ch. 14 - Prob. 3ECh. 14 - Prob. 4E
Ch. 14 - More tips The waiter in Exercise 3 usually waits...Ch. 14 - More groceries Suppose the store in Exercise 4 had...Ch. 14 - Prob. 7ECh. 14 - t-models, part II Using the t tables, software, or...Ch. 14 - t-models, part III Describe how the shape, center,...Ch. 14 - Prob. 10ECh. 14 - Prob. 11ECh. 14 - Home sales again In the previous exercise, you...Ch. 14 - Prob. 13ECh. 14 - Salaries A survey finds that a 95% confidence...Ch. 14 - Cattle Livestock are given a special feed...Ch. 14 - Prob. 16ECh. 14 - Prob. 17ECh. 14 - Student survey revisited Chapter 2, Exercise 86...Ch. 14 - Prob. 19ECh. 14 - Prob. 20ECh. 14 - Meal plan After surveying students at Dartmouth...Ch. 14 - Prob. 22ECh. 14 - Prob. 23ECh. 14 - Crawling Data collected by child development...Ch. 14 - Prob. 25ECh. 14 - Credit card charges A credit card company takes a...Ch. 14 - Prob. 27ECh. 14 - Pulse rates In the latest National Health and...Ch. 14 - Prob. 29ECh. 14 - Parking Hoping to lure more shoppers downtown, a...Ch. 14 - Prob. 31ECh. 14 - Prob. 32ECh. 14 - Speed of light In 1882, Michelson measured the...Ch. 14 - Michelson After his first attempt to determine the...Ch. 14 - Prob. 35ECh. 14 - Prob. 36ECh. 14 - Prob. 37ECh. 14 - Hot dogs A nutrition lab tested 40 hot dogs to see...Ch. 14 - Prob. 39ECh. 14 - Prob. 40ECh. 14 - Prob. 41ECh. 14 - Computer lab fees The technology committee has...Ch. 14 - Prob. 43ECh. 14 - CEO compensation The total compensation of the...Ch. 14 - Prob. 45ECh. 14 - CEOs, revisited In Exercise 44, you looked at the...Ch. 14 - GPAs A colleges data about the incoming freshmen...Ch. 14 - Prob. 48ECh. 14 - Lucky spot? A reporter working on a story about...Ch. 14 - Prob. 50ECh. 14 - Pregnancy Assume that the duration of human...Ch. 14 - Rainfall Statistics from Cornells Northeast...Ch. 14 - Prob. 53ECh. 14 - Prob. 54ECh. 14 - Prob. 55ECh. 14 - Doritos Some students checked 6 bags of Doritos...Ch. 14 - Prob. 57ECh. 14 - Prob. 58ECh. 14 - Chips Ahoy! In 1998, as an advertising campaign,...Ch. 14 - Yogurt Consumer Reports tested 11 brands of...Ch. 14 - Prob. 61ECh. 14 - Prob. 62ECh. 14 - Prob. 63ECh. 14 - Wind power Should you generate electricity with...
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