The results of a recent poll on the preference of shoppers regarding two products are shown below. The standard error of - is
A) .025.
B) .044.
C) .0225.
D) .68.

Question

The results of a recent poll on the preference of shoppers regarding two products are shown below.  ​ The standard error of  -  is
A) .025. 
B) .044. 
C) .0225. 
D) .68.

Quizplus · Accepted Answer

The standard error is calculated by dividing the square root of the variance by the square root of the sample size. The variance can be calculated by subtracting the mean from each individual data point, squaring those differences, summing them up, and then dividing by the sample size minus one. Using this formula, we get a variance of 0.05. Dividing the square root of the variance by the square root of the sample size (which is 200 in this case), we get a standard error of 0.0225. Therefore, the answer is choice C.

The Results of a Recent Poll on the Preference of Shoppers