Permutations are for lists (order matters) and combinations are for groups (order doesn’t matter).If you have to choose among 5 pizzas of a menu, two of them and it is a combination (which one you choose is irrelevant ) then you do have \(\frac{5*4*3*2*1}{2*1*3*2*1}\).

Permutation the order matters. If you have to choose margherita as first choice and pepperoni as a second choice then you do have : \(5*4\)

Hope it helps

Regards

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