I'll write the formula here, but then we'll think about what it's actually saying. This is 60 factorial over 60 minus 4 factorial divided also by 4 factorial, or in the denominator, multiplied by 4 factorial. This is the formula right here. What this is really saying, this part right here, 60 factorial divided by 60 minus 4 factorial, that's just 60 times 59 times 58 times 57. That's what this expression right here is. And if you think about it, the first number you pick, there's one of 60 numbers, that number is kind of out of the game, then you can pick from one of 59, then from one of 58, then of one of 57. So if you cared about order, this is the number of permutations you could pick four items out of 60 without replacing them.