| 30000 | ( | 10 | + | m | ) | + | ( | 18000 | + | 1000 | m | ) | ( | 15 | − | m | ÷ | 5 | ) | = | 558000 |
| 方程左边 = | 30000 | × | 10 | + | 30000 | m | + | ( | 18000 | + | 1000 | m | ) | ( | 15 | − | m | ÷ | 5 | ) |
| = | 300000 | + | 30000 | m | + | ( | 18000 | + | 1000 | m | ) | ( | 15 | − | m | ÷ | 5 | ) |
| = | 300000 | + | 30000 | m | + | 18000 | ( | 15 | − | m | ÷ | 5 | ) | + | 1000 | m | ( | 15 | − | m | ÷ | 5 | ) |
| = | 300000 | + | 30000 | m | + | 18000 | × | 15 | − | 18000 | m | ÷ | 5 | + | 1000 | m | ( | 15 | − | m | ÷ | 5 | ) |
| = | 300000 | + | 30000 | m | + | 270000 | − | 3600 | m | + | 1000 | m | ( | 15 | − | m | ÷ | 5 | ) |
| = | 570000 | + | 26400 | m | + | 1000 | m | ( | 15 | − | m | ÷ | 5 | ) |
| = | 570000 | + | 26400 | m | + | 1000 | m | × | 15 | − | 1000 | m | m | ÷ | 5 |
| = | 570000 | + | 26400 | m | + | 15000 | m | − | 200 | m | m |
| = | 570000 | + | 41400 | m | − | 200 | m | m |
| 570000 | + | 41400 | m | − | 200 | m | m | = | 558000 |