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This was the test question: Coriane wanted an A on her physics test. She needed 24 more points to get an A, which is 90%. What score did she get?

The multiple choices were 66%, 76%, 90%, or 114%. Which would you choose?

The maker of the test claimed that the answer was 66%....BUT, I beg to differ here!

If Coriane got X points originally out of T total points, we want (X+24)/T = .9, or X = .9T-24.

So, there are multiple answers...she could have gotten 3 out of 30 originally, or 12 out of 40, or 21 out of 50...or even 57 out of 90 (one of the possible "wrong" answers.

When will we learn that there is a difference between raw scores and percentages?

Reminds me of the teacher who gave this question on an end-of-year exam: BETH HAD SCORES OF 79, 83, AND 81 ON THREE TESTS. WHAT WAS HER AVERAGE MARK?

And, the student responded B-. What amount of credit (on any rubric) would you give the student?