A class average increases from 78 to 84 after adding scores. What happened to the mean?

A class average increases from 78 to 84 after adding scores. What happened to the mean?

• A. Stayed the same
• B. Increased by 6
• C. Decreased by 6
• D. Increased by 4

Answer: (B)

The mean is the sum of all scores divided by how many scores there are. When you add more scores, you increase both the total and the count. If the average goes from 78 to 84, the change in the mean is 84 minus 78, which equals 6. So the mean increases by 6 points. This upward shift happens because the new scores added were, on average, higher than the old mean, pulling the overall average up. The exact number and values of the added scores aren’t specified, but the change in the mean is simply 6.

The mean is the sum of all scores divided by how many scores there are. When you add more scores, you increase both the total and the count. If the average goes from 78 to 84, the change in the mean is 84 minus 78, which equals 6. So the mean increases by 6 points. This upward shift happens because the new scores added were, on average, higher than the old mean, pulling the overall average up. The exact number and values of the added scores aren’t specified, but the change in the mean is simply 6.