Destroyer QR 20 and 27

The main difference between permutations and combinations is that combinations will be forming groups of something. This basically says that you are putting things together. That is why when your looking for the different amount of ways that 8 horses could finish in first, second and third place your not putting the horses into groups instead your just arranging them, thus you will use permutation. However in the other problem you are making a 3 balloon bouquet or a group of ballons thus you will be using combinations. Hope that helps!