Considering the margin of error of a confidence interval, it is found that the correct option is:
It would be half as wide.
<h3>What is the margin of error of a confidence interval?</h3>
It is modeled by:
In which:
z is the critical value.
s is the standard deviation.
n is the sample size.
From this, we get that the margin of error is inversely proportional to the square root of the sample size. Then, multiplying the sample size by 4, when it changes from 50 to 200, cuts the margin of error in half, making the interval half as wide.