0.072 is the margin of error.
<h3>What is standard error?</h3>The standard error (SE) of a statistic is the standard deviation of its sampling distribution or an estimate of that standard deviation.
According to the question,
In a random sample of 250 students,
p= 0.98 (or 98%) were in favor of longer hours at the school library.
The standard error of p(the sample proportion) is (approximately)
The standard error of p =
p = 0.98
1 - p = 1 - 0.98 = 0.02
Here,
n = 250
The standard error of p =
The standard error of p ≈ 0.072
Therefore,
The margin of error is 0.072.
Learn more about is standard error here:
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