LOL! I know he's a PhD and a sharp guy, but I don't think math is his strong suit. It certainly isn't mine. Once we were trying to figure out what year something happened, and I told him he could probably figure it out faster than I could. We both sat there basically counting on our fingers, and came up with the year at the same time. That's OK - as long as he knows psych, we can always use a calculator for the math stuff.