| ( | 1 | + | m | ÷ | 2 100 | ) | × | 1000 | ( | 1 | + | m% | ) | × | 500 | = | 660000 |
| 方程左边 = | ( | 1 | + | m | ÷ | 2 100 | ) | × | 500000 | ( | 1 | + | m% | ) |
| ( | 1 | + | m | ÷ | 2 100 | ) | × | 500000 | ( | 1 | + | m% | ) | = | 660000 |
| 方程左边 = | 1 | × | 500000 | ( | 1 | + | m% | ) | + | m | ÷ | 2 100 | × | 500000 | ( | 1 | + | m% | ) |
| = | 500000 | ( | 1 | + | m% | ) | + | m | × | 25000000 | ( | 1 | + | m% | ) |
| = | 500000 | × | 1 | + | 500000 | × | m% | + | m | × | 25000000 | ( | 1 | + | m% | ) |
| = | 500000 | + | 5000 | m | + | m | × | 25000000 | ( | 1 | + | m% | ) |
| = | 500000 | + | 5000 | m | + | m | × | 25000000 | × | 1 | + | m | × | 25000000 | × | m% |
| = | 500000 | + | 5000 | m | + | m | × | 25000000 | + | m | × | 250000 | m |
| = | 500000 | + | 25005000 | m | + | m | × | 250000 | m |
| 500000 | + | 25005000 | m | + | m | × | 250000 | m | = | 660000 |