計算方法很多：

1:(5 + 7) ÷ 5 × 10

2:((5 + 7) ÷ 5) × 10

3:(5 + 7) ÷ (5 ÷ 10)

4:(5 + 7) × 10 ÷ 5

5:((5 + 7) × 10) ÷ 5

6:(5 + 7) × (10 ÷ 5)

7:10 ÷ 5 ×(5 + 7)

8:(10 ÷ 5) × (5 + 7)

9:10 ÷ (5 ÷ (5 + 7))

10:(10 × (5 + 7)) ÷ 5

11:10 × (5 + 7) ÷ 5

12:10 × ((5 + 7) ÷ 5)

13:10 ÷ 5 ×(7 + 5)

14:(10 ÷ 5) × (7 + 5)

15:10 ÷ (5 ÷ (7 + 5))

16:(10 × (7 + 5)) ÷ 5

17:10 × (7 + 5) ÷ 5

18:10 × ((7 + 5) ÷ 5)

19:(7 + 5) ÷ 5 × 10

20:((7 + 5) ÷ 5) × 10

21:(7 + 5) ÷ (5 ÷ 10)

22:(7 + 5) × 10 ÷ 5

23:((7 + 5) × 10) ÷ 5

24:(7 + 5) × (10 ÷ 5)