A researcher wishes to estimate the average number of minutes per day a person spends on the Internet. How large a sample must she select if she wishes to be 90% confident that the population mean is within 7 minutes of the sample mean? Assume the population standard deviation is 42 minutes. Round your final answer up to the next whole number. The researcher needs a sample of at least ______ people.
Added by Meghan S.
Step 1
Step 1: Calculate the margin of error using the formula: Margin of Error = Critical Value * (Population Standard Deviation / sqrt(sample size)) Show more…
Show all steps
Close
Your feedback will help us improve your experience
Marc Lauzon and 84 other Intro Stats / AP Statistics educators are ready to help you.
Ask a new question
Labs
Want to see this concept in action?
Explore this concept interactively to see how it behaves as you change inputs.
Key Concepts
Recommended Videos
A researcher wishes to estimate the average number of minutes per day a person spends on the Internet. How large a sample must she select if she wishes to be 99% confident that the population mean is within 8 minutes of the sample mean? Assume the population standard deviation is 47 minutes. Round your final answer up to the next whole number. The researcher needs a sample of at least ____people.
Lien L.
Internet Viewing A researcher wishes to estimate the average number of minutes per day a person spends on the Internet. How large a sample must she select if she wishes to be 99% confident that the population mean is within 7 minutes of the sample mean? Assume the population standard deviation is 41 minutes. Round your final answer up to the next whole number. The researcher needs a sample of at least people?
Qudsiya A.
Use the following information to answer the next seven exercises: The U.S. Census Bureau conducts a study to determine the time needed to complete the short form. The Bureau surveys 200 people. The sample mean is 8.2 minutes. There is a known standard deviation of 2.2 minutes. The population distribution is assumed to be normal. Which distribution should you use for this problem?
Confidence Intervals
A Single Population Mean using the Normal Distribution
Recommended Textbooks
Elementary Statistics a Step by Step Approach
The Practice of Statistics for AP
Introductory Statistics
Transcript
18,000,000+
Students on Numerade
Trusted by students at 8,000+ universities
Watch the video solution with this free unlock.
EMAIL
PASSWORD