You start by the easiest fraction: 41/100, then factor by primes: 100 = 2*2*5*5 then check if 41 can be factorized by these numbers (41/5, 41/2) since this doesn't work, the simplest form of 41% is: 41/100.
Ps. since 41 is a prime number you can just immediately tell that 41/100 is as far as you can go.
