An advertising executive wants to estimate the mean amount of time that consumers spend with digital media daily. From past studies, the standard deviation is estimated as 51 minutes. a. What sample size is needed if the executive wants to be 90% confident of being correct to within ±5 minutes? b. If 95% confidence is desired, how many consumers need to be selected?

An advertising executive wants to estimate the mean amount of time that consumers spend with digital media daily. From past studies, the standard deviation is estimated as 51 minutes. a. What sample size is needed if the executive wants to be 90% confident of being correct to within ±5 minutes? b. If 95% confidence is desired, how many consumers need to be selected?

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

An economist would like to estimate the mean amount of money that afamily spends to within $36. If the amount spent by a family isconsidered to be normally distributed with a standard deviation of $200,what sample size would be necessary to be 91% confident? Draw the graph.
A study reported on essential organic molecules and a Normal model can be used to describe these levels in adults. If the mean is 194 mg/dL and a standard deviation is 28, complete the following questions. a) Draw and label the Normal model. b) What percent of adults do you expect to have this essential organic molecule, cholesterol, levels over 210 mg/dL? c) What percent of adults do you expect to have cholesterol levels between 150 and 170 mg/dL? d) Estimate the interquartile range of cholesterol levels. IQR=___________mg/dL e) Above what value are the highest 15% of adults' cholesterol levels? ___________mg/dL
A quantitative data set has size 50. At least how many observations lie within three standard deviations to either side of the mean?
A sample of data is given as below:3, 5, 7. What is the standard deviation?
The sample standard deviation is a measure of what?
The manager of a major retail store has taken a random sample of 25 customers. The average sale was $52.50. The population standard deviation is known to be $6.10. The manager would like to determine whether or not the mean sales by all customers are significantly more than $50. What is the p-value for the test?
Suppose the durations of human pregnancies follow a mound-shaped distribution with a mean of 266 days and a standard deviation of 18 days. a. Approximately what percentage of human pregnancies last between 248 and 284 days? b. Between what two values will the durations of 95% of all human pregnancies fall? Answer in days
1. According to one study, the average hours of sleep on a weeknight for men was 6.9 hours with a standard deviation of 1.5 hours. a. Find the proportion of men who sleep for more than 8 hours per night. b. Find the proportion of men who sleep for less than 6 hours per night. c. Find the proportion of men who sleep between 6-8 hours per night. d. Find the number of hours that represents the 90th percentile.
Consider the following sample: 1, 4, 7, 2, 6. How does the standard deviation change when the 7 is replaced with a 12? Answer intuitively first, and then check your answers numerically.
As reported in Runner's World magazine, the times of the finishers in the New York City 10- km run are normally distributed with mean 61 minutes and standard deviation 9 minutes. The 75th percentile for the finishing times is 67 minutes. What is the interpretation of this value?
Given the sample data {1, 1, 3, 4, 6}.Calculate the mean.Calculate the standard deviation.
Is a measure of 29 inches "far away" from a mean of 19 inches? Suppose the data come from a sample whose standard deviation is 2 inches. A. How many standard deviation is 29 inches from 19 inches? b. Is 29 inches far away from a mean of 19 inches? c. Suppose the standard deviation of the underlying data is 7 inches. Is 29 inches far away from a mean of 19 inches?

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

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

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

GET THE APP

About FAQ Academic Integrity Sitemap Document Sitemap

Contact Bartleby Contact Research (Essays)High School Textbooks Literature Guides Concept Explainers by Subject Essay Help Mobile App

GET THE APP

Privacy

Your CA Privacy Rights

Your NV Privacy Rights

Cookie Policy

About Ads

Manage My Data

bartleby, a Learneo, Inc. business

a.	What sample size is needed if the executive wants to be 90% confident of being correct to within ±5 minutes?
b.	If 95% confidence is desired, how many consumers need to be selected?