# math

posted by .

The image of the public library is constantly changing, and their online services continue to grow. Usage of the library's home page grew by 17% during the past 12 months. It has been estimated that the current average length of a visit to the library's homepage is approximately 20 minutes. The library wants to take a sample to statistically estimate this mean. How large will the sample need to be to estimate the mean within 0.2 of 1 standard deviation with 0.95 confidence? (Round you answer up to the nearest whole number.)

Can someone help with formula for this and what do you use the percentage for on this one?

## Similar Questions

1. ### english

How might you explain to a new student of English what is happening in such sentences as these?
2. ### English

1. We should not scribble in books in the library. 2. We should not write down in books in the library. 3. We should not make a noise in the library. 4. We should not walk making sounds in the library. 5. We should not tear books in …
3. ### ON LINE LIBRARY SOURCES

HOW CAN THE ONLINE LIBRARY HELP ME WITH FINDING MY ACEDEMIC WRITING?
4. ### Literacy

4. Which of the following would be the best way to get to a list of encyclopedias that are available on the Web?
5. ### Information Leteracy

Which of the following would be the best way to get to a list of encyclopedias that are available on the Web?
6. ### Math

The image of the public library is constantly changing, and their online services continue to grow. Usage of the library's home page grew by 17% during the past 12 months. It has been estimated that the current average length of a …
7. ### math, statistics

The image of the public library is constantly changing, and their online services continue to grow. Usage of the library's home page grew by 17% during the past 12 months. It has been estimated that the current average length of a …
8. ### Stat, Math

The image of the public library is constantly changing, and their online services continue to grow. Usage of the library's home page grew by 17% during the past 12 months. It has been estimated that the current average length of a …
9. ### Statistics

The image of the public library is constantly changing, and their online services continue to grow. Usage of the library's home page grew by 17% during the past 12 months. It has been estimated that the current average length of a …
10. ### Economic

List five public goods you have utilized in the past month. Put a yes or no next to each, indicating if this public good could have been obtained through the private sector. Ans: Highway-no Healthcare-yes Library- no Theater-no Golf …

More Similar Questions