Answer:
12 and 8
Step-by-step explanation:
The following 6 outcomes add 7: {1, 6}, {2,5}, {3,4}, {4,3}, {5,2} and {6,1}
The following 1 outcome adds 12: {6, 6}
The following 5 outcomes add 8: {2,6}, {3,5}, {4,4}, {5,3} and {6,2}
Therefore the pair 12 and 8 would make the game fair, because both players have 6 favourable outcomes