Tell whether each situation is a permutation or combination.
How many 3-digit numbers can you write using the digits $6,7,$ and 8 exactly once in each number?
So we're making three digit numbers here and we can't duplicate digits of. We have to keep in mind the order because putting the numbers and one order versus another order makes that a different number. So this is gonna be a permutation, because my order is important and I have three numbers and I want three digit numbers from those three numbers, so that's just gonna be three times two times one or six ways that I can use those three digits to make.