“21点”游戏，用下列各组凑成24(每次只能用一次)写出公式2678 3377。

1: (2 - 6 + 7) × 8

2: ((2 - 6) + 7) × 8

3: (2 - (6 - 7)) × 8

4: (2 + 7 - 6) × 8

5: ((2 + 7) - 6) × 8

6: (2 + (7 - 6)) × 8

7: (2 × (7 + 8)) - 6

8: 2 × (7 + 8) - 6

9: (2 × (8 + 7)) - 6

10: 2 × (8 + 7) - 6

11: (7 + 2 - 6) × 8

12: ((7 + 2) - 6) × 8

13: (7 + (2 - 6)) × 8

14: (7 - 6 + 2) × 8

15: ((7 - 6) + 2) × 8

16: (7 - (6 - 2)) × 8

17: (7 + 8) × 2 - 6

18: ((7 + 8) × 2) - 6

19: 8 × (2 - 6 + 7)

20: 8 × ((2 - 6) + 7)

21: 8 × (2 - (6 - 7))

22: 8 × (2 + 7 - 6)

23: 8 × ((2 + 7) - 6)

24: 8 × (2 + (7 - 6))

25: (8 + 7) × 2 - 6

26: ((8 + 7) × 2) - 6

27: 8 × (7 + 2 - 6)

28: 8 × ((7 + 2) - 6)

29: 8 × (7 + (2 - 6))

30: 8 × (7 - 6 + 2)

31: 8 × ((7 - 6) + 2)

32: 8 × (7 - (6 - 2))

3、3、7和7的24个答案:

1: (3 + 3 ÷ 7) × 7

2: (3 + (3 ÷ 7)) × 7

3: (3 ÷ 7 + 3) × 7

4: ((3 ÷ 7) + 3) × 7

5: 7 × (3 + 3 ÷ 7)

6: 7 × (3 + (3 ÷ 7))

7: 7 × (3 ÷ 7 + 3)

8: 7 × ((3 ÷ 7) + 3)