“二十一点”游戏，用下列数字拼成24(每个数字只能用一次)，写出公式。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)