Combination number calculation imagine 2 brackets around bot

Combination number calculation (imagine 2 brackets around both numbers)
10
4
= 210

* n choose r means the total # of different ways to elect r elements from a set of n elements without order restriction. *
I think this seems fairly easy, but I wanted to make sure I was doing this correctly. So, with that being said, would I solve this the following way....

10 = 10 x 9 x 8 x 7
4 = 4 x 3 x 2 x 1
after simplyifying... i would reach the 210, correct?

This works with any set of 2 numbers, correct?

Solution