Essential Statistics
2nd Edition
ISBN: 9781259570643
Author: Navidi
Publisher: MCG
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Question
Chapter 7.2, Problem 18E
a.
To determine
Obtain a 98% confidence interval for the population
b.
To determine
Explain whether the confidence interval be narrower or wider when the sample size is
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1. A consumer group claims that the mean annual consumption of cheddar cheese by a person in
the United States is at most 10.3 pounds. A random sample of 100 people in the United States has
a mean annual cheddar cheese consumption of 9.9 pounds. Assume the population standard
deviation is 2.1 pounds. At a = 0.05, can you reject the claim? (Adapted from U.S. Department of
Agriculture)
State the hypotheses:
Calculate the test statistic:
Calculate the P-value:
Conclusion (reject or fail to reject Ho):
2. The CEO of a manufacturing facility claims that the mean workday of the company's assembly
line employees is less than 8.5 hours. A random sample of 25 of the company's assembly line
employees has a mean workday of 8.2 hours. Assume the population standard deviation is 0.5
hour and the population is normally distributed. At a = 0.01, test the CEO's claim.
State the hypotheses:
Calculate the test statistic:
Calculate the P-value:
Conclusion (reject or fail to reject Ho):
Statistics
21.
find the mean.
and
variance of the
following:
Ⓒ x(t) = Ut +V, and V indepriv. s.t
U.VN NL0, 63).
X(t) = t² + Ut +V, U and V incepires have N (0,8)
Ut
①xt = e UNN (0162)
~ X+ = UCOSTE, UNNL0, 62)
SU, Oct
⑤Xt=
7
where U. Vindp.rus
+> ½
have NL, 62).
⑥Xn = ΣY, 41, 42, 43, ... Yn vandom sample
K=1
Text
with mean zen and variance 6
Chapter 7 Solutions
Essential Statistics
Ch. 7.1 - Prob. 1CYUCh. 7.1 - Prob. 2CYUCh. 7.1 - Prob. 3CYUCh. 7.1 - Prob. 4CYUCh. 7.1 - Prob. 5CYUCh. 7.1 - Prob. 6CYUCh. 7.1 - Prob. 7CYUCh. 7.1 - Prob. 8CYUCh. 7.1 - Prob. 9CYUCh. 7.1 - 10. Using the output in Exercise 9:
Find the...
Ch. 7.1 - Prob. 11CYUCh. 7.1 - 12. The researchers now plan to construct a 99%...Ch. 7.1 - Prob. 13CYUCh. 7.1 - 14. An IQ test is designed to have scores that...Ch. 7.1 - Prob. 15CYUCh. 7.1 - Prob. 16CYUCh. 7.1 - In Exercises 17–20, fill in each blank with the...Ch. 7.1 - In Exercises 17–20, fill in each blank with the...Ch. 7.1 - Prob. 19ECh. 7.1 - In Exercises 17–20, fill in each blank with the...Ch. 7.1 - In Exercises 21–24, determine whether the...Ch. 7.1 - Prob. 22ECh. 7.1 - Prob. 23ECh. 7.1 - Prob. 24ECh. 7.1 - Prob. 25ECh. 7.1 - In Exercises 25–28, find the critical value zα∕2...Ch. 7.1 - Prob. 27ECh. 7.1 - Prob. 28ECh. 7.1 - Prob. 29ECh. 7.1 - In Exercises 29–32, find the levels of the...Ch. 7.1 - Prob. 31ECh. 7.1 - Prob. 32ECh. 7.1 - Prob. 33ECh. 7.1 - Prob. 34ECh. 7.1 - Prob. 35ECh. 7.1 - 36. A sample of size n = 64 is drawn from a...Ch. 7.1 - 37. A sample of size n = 10 is drawn from a normal...Ch. 7.1 - 38. A sample of size n = 80 is drawn from a normal...Ch. 7.1 - Prob. 39ECh. 7.1 - Prob. 40ECh. 7.1 - Prob. 41ECh. 7.1 - Prob. 42ECh. 7.1 - 43. SAT scores: A college admissions officer takes...Ch. 7.1 - Prob. 44ECh. 7.1 - Prob. 45ECh. 7.1 - Prob. 46ECh. 7.1 - Prob. 47ECh. 7.1 - Prob. 48ECh. 7.1 - Prob. 49ECh. 7.1 - Prob. 50ECh. 7.1 - Prob. 51ECh. 7.1 - Prob. 52ECh. 7.1 - Prob. 53ECh. 7.1 - Prob. 54ECh. 7.1 - Prob. 55ECh. 7.1 - 56. Different standard deviations: Martin and...Ch. 7.1 - Prob. 57ECh. 7.1 - Prob. 58ECh. 7.1 - Prob. 59ECh. 7.1 - Prob. 60ECh. 7.1 - Prob. 61ECh. 7.1 - Prob. 62ECh. 7.1 - Prob. 63ECh. 7.1 - Prob. 64ECh. 7.1 - Interpret computer output: The following MINITAB...Ch. 7.1 - Interpret computer output: The following MINITAB...Ch. 7.1 - Prob. 67ECh. 7.1 - Prob. 68ECh. 7.2 - Prob. 1CYUCh. 7.2 - Prob. 2CYUCh. 7.2 - 3. A potato chip company wants to evaluate the...Ch. 7.2 - Prob. 4CYUCh. 7.2 - Prob. 5CYUCh. 7.2 - Prob. 6CYUCh. 7.2 - Prob. 7ECh. 7.2 - In Exercises 7 and 8, fill in each blank with the...Ch. 7.2 - In Exercises 9 and 10, determine whether the...Ch. 7.2 - In Exercises 9 and 10, determine whether the...Ch. 7.2 - Prob. 11ECh. 7.2 - Prob. 12ECh. 7.2 - Prob. 13ECh. 7.2 - 14. A sample of size n = 22 is drawn from a normal...Ch. 7.2 - 15. A sample of size n = 12 is drawn from a normal...Ch. 7.2 - Prob. 16ECh. 7.2 - 17. A sample of size n = 15 has sample mean and...Ch. 7.2 - Prob. 18ECh. 7.2 - Prob. 19ECh. 7.2 - Prob. 20ECh. 7.2 - Prob. 21ECh. 7.2 - Prob. 22ECh. 7.2 - 23. Fake Twitter followers: Many celebrities and...Ch. 7.2 - Prob. 24ECh. 7.2 - Prob. 25ECh. 7.2 - 26. Sound it out: Phonics is an instructional...Ch. 7.2 - Prob. 27ECh. 7.2 - Prob. 28ECh. 7.2 - Baby weights: Following are weights, in pounds, of...Ch. 7.2 - Eat your cereal: Boxes of cereal are labeled as...Ch. 7.2 - Prob. 31ECh. 7.2 - Mortgage rates: Following are interest rates...Ch. 7.2 - Prob. 33ECh. 7.2 - Big salary for the boss: Following is the total...Ch. 7.2 - Prob. 35ECh. 7.2 - Prob. 36ECh. 7.2 - Prob. 37ECh. 7.2 - Sleeping outlier: A simple random sample of eight...Ch. 7.2 - Prob. 39ECh. 7.2 - Prob. 40ECh. 7.2 - Prob. 41ECh. 7.2 - Prob. 42ECh. 7.2 - Prob. 43ECh. 7.2 - Prob. 44ECh. 7.2 - Prob. 45ECh. 7.2 - Interpret computer output: The following MINITAB...Ch. 7.2 - Prob. 47ECh. 7.3 - A simple random sample of 200 third-graders in a...Ch. 7.3 - Prob. 2CYUCh. 7.3 - A pollster is going to sample a number of voters...Ch. 7.3 - Prob. 4CYUCh. 7.3 - Prob. 5CYUCh. 7.3 - In a simple random sample of 15 seniors from a...Ch. 7.3 - Prob. 7ECh. 7.3 - Prob. 8ECh. 7.3 - Prob. 9ECh. 7.3 - Prob. 10ECh. 7.3 - In Exercises 11–14, find the point estimate, the...Ch. 7.3 - In Exercises 11–14, find the point estimate, the...Ch. 7.3 - Prob. 13ECh. 7.3 - In Exercises 11–14, find the point estimate, the...Ch. 7.3 - In Exercises 15–18, use the given data to...Ch. 7.3 - In Exercises 15–18, use the given data to...Ch. 7.3 - Prob. 17ECh. 7.3 - Prob. 18ECh. 7.3 - Smart phone: Among 238 cell phone owners aged...Ch. 7.3 - Working at home: According to the U.S. Census...Ch. 7.3 - Sleep apnea: Sleep apnea is a disorder in which...Ch. 7.3 - Internet service: An Internet service provider...Ch. 7.3 - Volunteering: The General Social Survey recently...Ch. 7.3 - SAT scores: A college admissions officer sampled...Ch. 7.3 - WOW: In the computer game World of Warcraft, some...Ch. 7.3 - Contaminated water: In a sample of 42 water...Ch. 7.3 - Call me: A sociologist wants to construct a 95%...Ch. 7.3 - Reading proficiency: An educator wants to...Ch. 7.3 - Surgical complications: A medical researcher wants...Ch. 7.3 - Prob. 30ECh. 7.3 - Changing jobs: A sociologist sampled 200 people...Ch. 7.3 - Prob. 32ECh. 7.3 - Small sample: Eighteen concrete blocks were...Ch. 7.3 - Prob. 34ECh. 7.3 - Prob. 35ECh. 7.3 - Prob. 36ECh. 7.3 - Prob. 37ECh. 7.3 - Prob. 38ECh. 7.3 - Prob. 39ECh. 7.3 - Prob. 40ECh. 7.3 - Prob. 41ECh. 7.3 - Prob. 42ECh. 7.3 - Prob. 43ECh. 7.4 - Prob. 1CYUCh. 7.4 - Prob. 2CYUCh. 7.4 - Prob. 3CYUCh. 7.4 - In Exercises 1–4, state which type of parameter is...Ch. 7.4 - Prob. 5ECh. 7.4 - In Exercises 5–10, state which type of parameter...Ch. 7.4 - In Exercises 5–10, state which type of parameter...Ch. 7.4 - Prob. 8ECh. 7.4 - Prob. 9ECh. 7.4 - Prob. 10ECh. 7.4 - Prob. 11ECh. 7.4 - Prob. 12ECh. 7.4 - Prob. 13ECh. 7.4 - Credit card debt: In a survey of 1118 U.S. adults...Ch. 7.4 - Pneumonia: In a simple random sample of 1500...Ch. 7.4 - Prob. 16ECh. 7 - Prob. 1CQCh. 7 - Prob. 2CQCh. 7 - Prob. 3CQCh. 7 - Prob. 4CQCh. 7 - Prob. 5CQCh. 7 - Prob. 6CQCh. 7 - Prob. 7CQCh. 7 - Prob. 8CQCh. 7 - Prob. 9CQCh. 7 - Prob. 10CQCh. 7 - Prob. 11CQCh. 7 - Prob. 12CQCh. 7 - Prob. 13CQCh. 7 - Prob. 14CQCh. 7 - Prob. 15CQCh. 7 - Build more parking? A survey is to be conducted in...Ch. 7 - Drill lifetime: A sample of 50 drills had a mean...Ch. 7 - Cost of environmental restoration: In a survey of...Ch. 7 - More repairs: A sample of six records for repairs...Ch. 7 - Automobile pollution: In a random sample of 85...Ch. 7 - Contaminated water: Polychlorinated biphenyls...Ch. 7 - Defective electronics: A simple random sample of...Ch. 7 - Prob. 8RECh. 7 - High octane: Fifty measurements are taken of the...Ch. 7 - Super Bowl: A simple random sample of 140...Ch. 7 - Prob. 11RECh. 7 - Prob. 12RECh. 7 - Leaking tanks: Leakage from underground fuel tanks...Ch. 7 - Prob. 14RECh. 7 - Prob. 15RECh. 7 - Prob. 1WAICh. 7 - What factors can you think of that may affect the...Ch. 7 - Prob. 3WAICh. 7 - Prob. 4WAICh. 7 - Prob. 5WAICh. 7 - When constructing a confidence interval for μ, how...Ch. 7 - Prob. 1CSCh. 7 - Prob. 2CSCh. 7 - Prob. 3CSCh. 7 - Repeat Exercises 1 and 2 for the Year 2 data. The...Ch. 7 - Prob. 5CS
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