In 2015, the average duration of long-distance telephone calls from a certain town was 9.4minutes. A telephone company wants to perform a test to determine whether this averageduration of long-distance calls has changed. Twenty calls, originating from the town, wasrandomly selected and ine mean duration was 10.2 minutes with standard deviation 4.8minutes.b) Construct the 99% confidence interval for the population mean duration of the long-distance calls from the town.

The test statistic for one sample t-test is given by, The test statistic follows a t-distribution…

Answered: In 2015, the average duration of…

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

See similar textbooks

Similar questions

For a simple random sample of 40 Honda Accords (4 cylinder, 2.4 liter, 5-speedautomatic), the mean gas mileage was 23 miles per gallon with a standard deviation of 1.5miles per gallon. Construct a 95% confidence interval for the mean gas mileage of similar2005 Honda Accords.
A paint manufacturer wants to determine the average drying time of a new interior wall paint. If for 12 test areas of equal size he obtained a mean drying time of 66.3 minutes and a standard deviation of 8.4 minutes, conduct a 95% confidence interval for the true mean .
A study was conducted to estimate hospital costs for car accident victims who woreseat belts. Suppose that 46 randomly selected cases had an average of $15150and a standard deviation of $8500. If the average hospital costs for those that didnot wear seatbelts was $19000, construct a 90% confidence interval to see if theaverage costs are significantly different.
A trucking fleet-owner owns two semi-trucks and wishes to compare the amount of fuel used per week by the two vehicles. In a random sample of 100 weeks, truck #1 used a mean volume of 340 gallons with a standard deviation of 11 gallons. In a second, independent random sample of 100 weeks, truck #2 used a mean volume of 331 gallons with standard deviation 6 gallons.It is of interest to construct a confidence interval for the difference in population means using a confidence level of 90 percent. ?1−?2, where ?1 is the mean fuel volume used by truck #1 and ?2 is the mean volume of fuel used by truck #2. Note: 340−331=9 and 112100+62100‾‾‾‾‾‾‾‾‾‾‾√=1.25299640861417 Your answers below should be entered as numbers. Do not round during intermediate steps. If you round an answer, make sure you do so correctly and keep at least three decimal places. (a) The estimate is: gallons. (b) The standard error is: gallons. (c) The multiplier is: .
2.) From a simple random sample of 30 Honda Accords (4 cylinder, 2.4 liter, 5-speed automatic), the mean gas mileage was 23 miles per gallon with a standard deviation of 1.5 miles per gallon. Construct a 95% Confidence Interval for the mean gas mileage of similar 2005 Honda Accords.
In a study of 120 post-menopausal women on hormone replacement therapy (HRT), there was a mean systolic blood pressure of 131 mmHg, with a standard deviation of 16.5. Calculate a 95% confidence interval for the true mean SBP.
In a random sample of 36 criminals convicted of a certain crime, it was determined that the mean length of sentencing was 69 months, with a standard deviation of 11 months. Construct and interpret a 90% confidence interval for the mean length of sentencing for this crime.
A study conducted to examine the age of commercial jets in the United States sampled 36 planes and found the average age to be 12.6 years with a standard deviation of 2.7 a. Calculate and interpret a 90% confidence interval for the average age of commercial jets in the United States. b. A report in USA Today claimed that the mean age of commercial jets in the United States was 14 years. Using the confidence interval in (a), is there enough evidence to refute this claim?
In a sample of 31 patients, the amount of an anesthetic required to produce anesthesia suitable for surgery was found to have a standard deviation (from patient to patient) of 10.2 mg. Compute a 98% confidence interval on the population standard deviation.
In a large urban city, it was found that in a sample of 6 months, an average of 28 burglaries occurred each month, with a standard deviation of 4. Construct the 95% confidence interval for the true mean number of burglaries to occur in this city each month.
A random sample of 40 adults with no children under the age of 18 years results in a mean daily leisure time of 5.64 hours, with a standard deviation of 2.43 hours. A random sample of 40 adults with children under the age of 18 results in a mean daily leisure time of 4.09 hours, with a standard deviation of 1.63 hours. Construct and interpret a 90% confidence interval for the mean difference in leisure time between adults with no children and adults with children μ1−μ2.
In crash tests of 28 Honda Odyssey minivans, collision repair costs are found to have a distribution that is roughly bell-shaped, with a mean of $2020 and a standard deviation of $350. Construct the 98% confidence interval for the mean repair costs in all such vehicle collisions.

SEE MORE QUESTIONS

Recommended textbooks for you

MATLAB: An Introduction with Applications

Statistics

ISBN:

9781119256830

Author:

Amos Gilat

Publisher:

John Wiley & Sons Inc

Probability and Statistics for Engineering and th…

Statistics

ISBN:

9781305251809

Author:

Jay L. Devore

Publisher:

Cengage Learning

Statistics for The Behavioral Sciences (MindTap C…

Statistics

ISBN:

9781305504912

Author:

Frederick J Gravetter, Larry B. Wallnau

Publisher:

Cengage Learning

MATLAB: An Introduction with Applications

Statistics

ISBN:

9781119256830

Author:

Amos Gilat

Publisher:

John Wiley & Sons Inc

Probability and Statistics for Engineering and th…

Statistics

ISBN:

9781305251809

Author:

Jay L. Devore

Publisher:

Cengage Learning

Statistics for The Behavioral Sciences (MindTap C…

Statistics

ISBN:

9781305504912

Author:

Frederick J Gravetter, Larry B. Wallnau

Publisher:

Cengage Learning

Elementary Statistics: Picturing the World (7th E…

Statistics

ISBN:

9780134683416

Author:

Ron Larson, Betsy Farber

Publisher:

PEARSON

The Basic Practice of Statistics

Statistics

ISBN:

9781319042578

Author:

David S. Moore, William I. Notz, Michael A. Fligner

Publisher:

W. H. Freeman

Introduction to the Practice of Statistics

Statistics

ISBN:

9781319013387

Author:

David S. Moore, George P. McCabe, Bruce A. Craig

Publisher:

W. H. Freeman

SEE MORE TEXTBOOKS