How many different combinations of four numbers are there?

Answer:
9999 + 1

* * * * *

That is so wrong!

There are 10*9*8*7/(4*3*2*1) = 210 combinations of 4 numbers from the set of ten 1-digit numbers, 0 1, 2, ... 9

When considering combinations, 1234 is the same as 2314 or 4123 etc.
First answer by Hrolfk. Last edit by Mehtamatics. Contributor trust: 611 [recommend contributor recommended]. Question popularity: 1 [recommend question].