@SouthernAtHeart,
I’m not sure that was correct,
If he plays 328 more games, but he only wins 64% of the time, he would only win 210 of those games, so
6200 + 210 / 10,000 + 328 = 0.6208
If seems like it should be something like this, but I don’t know how or if you can solve it mathematically. I’m sure you can somehow.
6200 + (.64 x Z) / 10,000 + (.64 x Z) > 0.63