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

Hello rookie here,
I was wondering how in selecting a duo, one lead and one supporting actor could end up in permutations, because having the duo selected in any order does not matter so why would I use permutation.

We can simply apply multiplication principle here!

Since we need to pick two different candidates of 6, this can be done in \((6)(5) = 30\) ways

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