4 mental math questions. Stuff like 37 times 37. How many 27-cent stamps can you buy with $10, etc. Then he asked how confident (in a probability) I was that I got them all right, how confident I was I got the hardest one right, and how confident I was I got at least one wrong. After, he asked me a coin problem: What is the probability you get exactly 2 heads in 4 flips of a coin.