Would you have allowed this?

[Falkus]

If he doesn't have skill pints in Knowlege(math), then he can only use an intelligence check for really easy questions(DC 10).

I really hate this fad of making up new skills. Mathematics easily falls under the domain of architecture or even just being a mage. Making up new skills is a bad thing, because it makes skill points less valuable, especially knowledge skills, which are supposed to be broad and sweeping, not extremely specific. There's a reason why its knowledge (planes), instead of a seperate knowledge skill for each different plane.