What is a decent number of questions to complete the solve?

[Gomer1228]

Is 15-20 good, under 25, 30?

I've only played a few times solo and my number of questions to solve varies greatly.

[Clearly Toughpick]

Based on statistics for all players, the average number of questions asked by winners is nine. But I think the typical game here is a two player game, so they may have access to eight, nine or ten answers to the questions of their opponent. So about 18 questions in all. Someone, please poke holes in my logic!