A study of five hundred adults found that the number of hours they spend on social networking sites each week is normally distributed with a mean of 14 hours. The population standard deviation is 3 hours. What is the margin of error for a 95% confidence interval?

0.134

0.220

0.263

0.313

Question

A study of five hundred adults found that the number of hours they spend on social networking sites each week is normally distributed with a mean of 14 hours. The population standard deviation is 3 hours. What is the margin of error for a 95% confidence interval?

 0.134

 0.220

 0.263

 0.313

ganeshie8 · Answer

Margin of error for 95% CI =  $\large 1.96 \times \frac{\sigma}{\sqrt{n}}$

ganeshie8 · Answer

plugin given values and simplifyy

ganeshie8 · Answer

http://www.wolframalpha.com/input/?i=1.96*3%2Fsqrt%28500%29