It was embarrassing when I posed my own question to him, 10 + 5 - 1 - 4 + 5, and he answered 15 before I could tell if he was right. I want a refund on my college tuition.
I have literally hit my forehead with the palm of my right hand. Yes, learning to add and subtract single-digit numbers very fast is a critical aspect of college education, and if a college fails to impart this vital skill on a student, then the entire thing was pointless.
Your headline is wrong, OP. The americunt in question (and probably you too) most definitely doesn't realize how stupid he is.