When you roll the dice, there are 36 possible outcomes. For each pipe, how many of those 36 allow you to select that pipe?

1: 11
2: 12
3: 13
4: 14
5: 15
6: 16
7: 6
8: 5
9: 4

So if I have the chance to choose 7, 8 or 9, I should prioritize that above the other options available for that roll.

This is because the numbers 1-6 are available on each single die, and 2-6 can also be available as sums of the two dice.