A random sample of 120 classrooms at a large university found that 70% of them had been cleaned
Properly. What is the standard error of the sample proportion?
A) 0.028
B) 0.458
C) 0.046
D) 0.042
E) 0.082

Question

Quizplus · Accepted Answer

The standard error of the sample proportion is:SE = sqrt(p * (1 - p) / n)where p is the sample proportion and n is the sample size.In this case, p = 0.7 and n = 120, so:SE = sqrt(0.7 * (1 - 0.7) / 120) = 0.042

A Random Sample of 120 Classrooms at a Large University