According to a national poll of 650 college students, 57% play video games more than 6 hours a week. Find the margin of error and the 95% confidence interval fo

Question

According to a national poll of 650 college students, 57% play video games more than 6 hours a week.
Find the margin of error and the 95% confidence interval for the survey. Give your answers as percentages rounded to the nearest tenth of a percent.

Answer 1

The error margin is 1.96 * sqrt (  57% * (1 - 57%) / 650 ) = 0.038 = 3.8%

 

 

The confidence interval is then 57% +or- 3.8% = (53.2, 60.8)

 

We are 95% certain the actual population proportion lies inside that interval.