Question

Michelle, a student studying music, randomly sampled fellow music majors and asked whether they listen to music while they study. The resulting confidence interval for the proportion of music students who listen to music while studying is (0.09,0.26). What is the margin of error?

Answer 1

The margin of error of this confidence interval is MOE=0.085.

Explanation:

The confidence interval bounds are usually calculated from a sample statistic substracting (for the lower bound) or adding (for the upper bound) the margin of error. This margin of error depends on the confidence level, the standard deviation and the sample size.

Then, if the lower and upper bound are calculated this way, we can calculate the margin of error as:

`LB=p-MOE\\\\UB=p+MOE\\\\UB-LB=(p+MOE)-(p-MOE)=2\cdot MOE\\\\\\MOE=(UB-LB)/(2)=(0.26-0.09)/(2)=(0.17)/(2)=0.085`