I just want to clarify if my understanding of the three is correct. I sometimes still confuse if I will use fundamental counting principle or (permutation or combination).
Is it correct to say that I will only use permutation or combination if I have to actually choose something? For example in a race the no. of ways to choose 1st 2nd and 3rd place from 20 racers is 20P3 right,20! ?
But for example the problem will state that in how many ways can 20 racers finish a race its 20! not 20P something or 20C something?