Question

Based on a poll, a newspaper reported that between 52% and 68% of voters would be likely to vote for a school bond issue. What is the margin of error of the poll? A) 8% B) 1096 C) 34% D) 26%

Answer 1

A) 8%

Explanation:

A confidence interval of proportions has an upper end and a lower end.

The margin of error is the difference between these points divided by two. Also, it is the upper end subtracted by the estimated proportion, or the estimated proportion subtracted by the lower end.

In this problem, we have that:

Upper end: 0.68

Lower end: 0.52

Margin of error

`M = (0.68 - 0.52)/(2) = 0.08`

The margin of error is 8%.

So the correct answer is:

A) 8%