It would take a while to list all of the possible three-digit number combinations but here is what I suggest you do.
In order to avoid confusion, take a number from the list (I suggest using the first number) and make all possible combinations just starting with the number. For example, I'll use the number 2. There are 12 different combinations you can make with the number 2 alone. 256, 258, 259, 265, 268, 269, 289, 285, 286, 298, 296, 295. Now repeat with the other numbers.
Hope this helps!