Well there's a finite number of canon but the way it's looking, fillers are continuing to grow at an infinite rate.
If u use the ratio of canon to filler as ur mark then u get canon/filler as your ratio
Considering that the anime is on going, we can take the limit as it approaches infinity since we have no indication if it will end
There fore u get a finite number over infinity which means that the lim as x->infinity is 0
Meaning that the number of canon episodes are insignificantly smaller than fillers