Probably mangled the expression. (0.95)^9 = 63%, 1 - (0.95)^9 = 37%

Hmm, (1 - (1-0.95))^9 also = 63%. No idea why 64, closest I can see is 1-(0.95)^20 or 1-(1-0.05)^20 = 64%.

Yeah, I thought he was talking about 1 out of 20 features, but that's kind of why I was wondering if AI had written it. Sometimes it'll have mis-aligned figures etc.