Immersion in alcohol generally does not enhance math skills.
My ex was like that - obsessing over details, insisting he was right. At one point we were arguing how to divide a divorce-related expense and he insisted in questioning my proposal for dividing it because I rounded up rather than down at the second decimal point. Yes, that's one-tenth of one percent, or 0.1 penny on the dollar. (And full disclosure, I argued back until I eventually realized "this is completely nuts and by contributing to the craziness I am staying engaged with a crazy person", and let him have his tenth of one percent).