Fair Price

A professor handed out the test to his students and returned to his desk
to wait. When the test was over, the students filed over and handed in
their papers.

As the professor was going through the submissions, he noticed one
student had taped a hundred dollar bill to his test. On the bill the
student had written 'A buck a point'.

The next day the professor handed back the tests.

The student who had attached the hundred also received an envelope
containing sixty-four dollars. On it was written 'Here's your change'.