When you look at the solution below will not be clear
1. 3 + [0] 3 = 3
2. 3 + [1] 3 = 4
3. 3 + [2] 3 = 5
4. 3 + [3] 3 = 6 or 3 +3 = 6
5.33Rd1 (6) d2 (7) +3 = 7
6.33Rd1 (6) d2 (8) +3 = 8
7.33Rd1 (6) d2 (9) +3 = 9
8.33Rd1 (6) d2 (10) +3 = 10
9.33Rd1 (6) d2 (12) +3 = 12
(1,2,3,4) - There are many...