The mean of the difference is equal to the mean of the difference .

Question

The mean of the difference  is equal to the mean of the difference  .

Quizplus · Accepted Answer

The two differences in question are:

11ea78b9_2e1f_08fb_8379_dbd07d929f97_TB4388_11 - 11ea78b9_2e1f_08fb_8379_dbd07d929f97_TB4388_11

and

11ea78b9_2e1f_08fc_8379_25f31981878c_TB4388_11 - 11ea78b9_2e1f_08fc_8379_25f31981878c_TB4388_11

It is obvious that both differences are equal to zero, so their mean is also zero. Therefore, the statement is true, and the answer should be A, but since it is not possible for both choices to be correct, we must conclude that the question is flawed.

The Mean of the Difference Is Equal to the Mean