Question 1202857
c(n,x) is the formul to use.
n is the number of possibe choices.
x is the number of choices to extract from that.
n = 16
4 = x
c(n,x) = n! / (x! * (n-x)!)
when n = 16 and x = 4, the equation becomes c(16,4) = 16! / (4! * 12!) = (16 * 15 * 14 * 13 * 12!) / (4! * 12!) = (16 * 15 * 14 * 13) / (4 * 3 * 2 * 1) = 1820.