| 4500 | × | 12 | × | 9 10 | − | 60 100 | × | 70 | X | ( | 49 1000 | + | 2 100 | ) | ÷ | 40 100 | × | 70 | X | + | 5 100 | × | 70 | = | 19 500 |
| 方程左边 = | 48600 | − | 7350 | X | ( | 49 1000 | + | 2 100 | ) | X | + | 7 2 | X |
| 48600 | − | 7350 | X | ( | 49 1000 | + | 2 100 | ) | X | + | 7 2 | X | = | 19 500 |
| 方程左边 = | 48600 | − | 7350 | X | × | 49 1000 | X | − | 7350 | X | × | 2 100 | X | + | 7 2 | X |
| = | 48600 | − | 7203 20 | X | X | − | 147 | X | X | + | 7 2 | X |
| 48600 | − | 7203 20 | X | X | − | 147 | X | X | + | 7 2 | X | = | 19 500 |