Posted by **Alia** on Saturday, January 12, 2013 at 12:22am.

Please forgive me for posting this for the 3rd time but I really need to learn this:

A researcher conducted a study of the access speed of 45 hard drives and concluded that his maximum error of estimate was 28. If he were to conduct a second study to reduce the maximum error of estimate to 7, about how many hard drives should he include in his new sample?

Select one:

a. 720

b. 45

c. 90

d. 180

Please can someone explain me how to do the above problem.

My working: 28/7 = 4, so 4^2=16

16 x 45 =720.

I am not sure if the above working is correct but please i really need help in learning this problem (question). So, Please can anyone assist me by showing the correct method for this.

Thanks.

## Answer This Question

## Related Questions

- Statistics & Probability - A researcher conducted a study of the access speed of...
- Statistics & Probability - A researcher conducted a study of the access speed of...
- statistics - A researcher conducted a study of the access speed of 40 hard ...
- statistics - A researcher wishes to estimate with 95% confidence the proportion ...
- English - I'll try to learn how to make a clear voice. I'll try to practice ...
- Statistics - A researcher wishes to estimate, with 95% confidence, the ...
- math - A computer store sold a total of 300 items last month. The store sold six...
- Algebra - Mitch has 3 tests to study for on Thursday night. He needs to spend ...
- statistics - A researcher wants to estimate the average time (in minutes) spent ...
- Statistics - A researcher wishes to estimate the proportion of adults who have ...

More Related Questions