So we can use the following digits: 4,5,6,7,8,9
and we need three numbers with 8 digits each. Here are some examples:
1)
45 678 999 (you can also write 45,678,999 for easier reading)
2) 44 456 789 (you can also write 44,456,789 for easier reading)
3)45 678 456 (or 45,678,456)
Answer:
-1/5 I believe, since you go down one and to the right by 5.
The number of combinations is the product of the number of choices for each selection...
c=11*10*49*48*47*46=559,352,640