**MEDAL/FAN
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

**MEDAL/FAN
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

anonymous · Answer

@ganeshie8 
@pooja195 
@Michele_Laino

michele_laino · Answer

Hint:
95% confidence interval, means that our variable has to be within an interval whose ends are:
$$\Large  \begin{gathered}
  14 - 1.96\sigma  = 14 - 1.96 \times 3 = ...? \hfill \
  14 + 1.96\sigma  = 14 + 1.96 \times 3 = ...? \hfill \ 
\end{gathered} $$

anonymous · Answer

So its 8.12 and 19.88

anonymous · Answer

@Michele_Laino is that right? Can you help me pls thats not an option