4, 6, 3, 9的24點答案：

1: 4 × (3 - 6 + 9)

2: 4 × ((3 - 6) + 9)

3: 4 × (3 - (6 - 9))

4: 4 × (3 + 9 - 6)

5: 4 × ((3 + 9) - 6)

6: 4 × (3 + (9 - 6))

7: 4 × (9 - 6 + 3)

8: 4 × ((9 - 6) + 3)

9: 4 × (9 - (6 - 3))

10: 4 × (9 + 3 - 6)

11: 4 × ((9 + 3) - 6)

12: 4 × (9 + (3 - 6))

13: (6 - 4) × (3 + 9)

14: (6 - 4) × (9 + 3)

15: (3 - 6 + 9) × 4

16: ((3 - 6) + 9) × 4

17: (3 - (6 - 9)) × 4

18: (3 + 9 - 6) × 4

19: ((3 + 9) - 6) × 4

20: (3 + (9 - 6)) × 4

21: (3 + 9) × (6 - 4)

22: (9 - 6 + 3) × 4

23: ((9 - 6) + 3) × 4

24: (9 - (6 - 3)) × 4

25: (9 + 3 - 6) × 4

26: ((9 + 3) - 6) × 4

27: (9 + (3 - 6)) × 4

28: (9 + 3) × (6 - 4)