Consider one bag:
Pick 10: 3 magic beans
Pick 9: 2 or 3 beans
Pick 8: 1, 2 or 3 beans
Pick 7: 0,1,2, or 3 beans
Pick 6: 0,1,2, or 3 beans
Pick 5: 0,1,2, or 3 beans
Pick 4: 0,1,2 or 3 beans
Pick 3:0,1,2, or 3 beans
Pick 2: 0,1,2 beans
Pick 1:0,1 beans
Pick 0: 0 beans
The...