I do not know, I was never fan of math. I think it is useless skill. But maybe... [His frown slowly makes way for an excited smile, and he slams a fist into the palm of his hand.] A-ha! That is the trial. We are meant to convince dragon his lessons are useless. And if he will not listen, then we fight him!

[He did it, he cracked the trial!! (Disclaimer: he did not crack the trial.)]