No one else was standing up to tackle the problem. The professor waited and waited. So I stood up. I would take up the chalk. I went up, took a bow for the applause, and began. In correctly. Yep, misinterpreted the problem from the very start. After that I got along a bit better and stumbled to the final number correctly. Which I then read backward and again was wrong.
Now everyone has another bit of argument against standing up.
I suppose I could tie the baseline psychological phenomena here to more important things like protesting tyranny, but somehow the a+b=c -> 10a+10b+10c thing never quite works.