| ( | 3500 | − | 20 | a | ) | × | 240 | ( | 1 | + | a% | ) | + | 3000 | ( | 1 | − | ( | a | ÷ | 2 | ) | × | 1 100 | ) | × | 360 | ( | 1 | + | ( | 2 | ÷ | 9 | × | a | + | 20 | ) | × | 1 100 | ) | = | 2067600 |
| 方程左边 = | ( | 3500 | − | 20 | a | ) | × | 240 | ( | 1 | + | a% | ) | + | 1080000 | ( | 1 | − | ( | a | ÷ | 2 | ) | × | 1 100 | ) | ( | 1 | + | ( | 2 | ÷ | 9 | × | a | + | 20 | ) | × | 1 100 | ) |
| ( | 3500 | − | 20 | a | ) | × | 240 | ( | 1 | + | a% | ) | + | 1080000 | ( | 1 | − | ( | a | ÷ | 2 | ) | × | 1 100 | ) | ( | 1 | + | ( | 2 | ÷ | 9 | × | a | + | 20 | ) | × | 1 100 | ) | = | 2067600 |
| 方程左边 = | 3500 | × | 240 | ( | 1 | + | a% | ) | − | 20 | a | × | 240 | ( | 1 | + | a% | ) | + | 1080000 | ( | 1 | − | ( | a | ÷ | 2 | ) | × | 1 100 | ) | ( | 1 | + | ( | 2 | ÷ | 9 | × | a | + | 20 | ) | × | 1 100 | ) |
| = | 840000 | ( | 1 | + | a% | ) | − | 4800 | a | ( | 1 | + | a% | ) | + | 1080000 | ( | 1 | − | ( | a | ÷ | 2 | ) | × | 1 100 | ) | ( | 1 | + | ( | 2 | ÷ | 9 | × | a | + | 20 | ) | × | 1 100 | ) |
| = | 840000 | × | 1 | + | 840000 | × | a% | − | 4800 | a | ( | 1 | + | a% | ) | + | 1080000 | ( | 1 | − | ( | a | ÷ | 2 | ) | × | 1 100 | ) | ( | 1 | + | ( | 2 | ÷ | 9 | × | a | + | 20 | ) | × | 1 100 | ) |
| = | 840000 | + | 8400 | a | − | 4800 | a | ( | 1 | + | a% | ) | + | 1080000 | ( | 1 | − | ( | a | ÷ | 2 | ) | × | 1 100 | ) | ( | 1 | + | ( | 2 | ÷ | 9 | × | a | + | 20 | ) | × | 1 100 | ) |
| = | 840000 | + | 8400 | a | − | 4800 | a | × | 1 | − | 4800 | a | × | a% | + | 1080000 | ( | 1 | − | ( | a | ÷ | 2 | ) | × | 1 100 | ) | ( | 1 | + | ( | 2 | ÷ | 9 | × | a | + | 20 | ) | × | 1 100 | ) |
| = | 840000 | + | 8400 | a | − | 4800 | a | − | 48 | a | a | + | 1080000 | ( | 1 | − | ( | a | ÷ | 2 | ) | × | 1 100 | ) | ( | 1 | + | ( | 2 | ÷ | 9 | × | a | + | 20 | ) | × | 1 100 | ) |
| = | 840000 | + | 3600 | a | − | 48 | a | a | + | 1080000 | ( | 1 | − | ( | a | ÷ | 2 | ) | × | 1 100 | ) | ( | 1 | + | ( | 2 | ÷ | 9 | × | a | + | 20 | ) | × | 1 100 | ) |
| = | 840000 | + | 3600 | a | − | 48 | a | a | + | 1080000 | × | 1 | ( | 1 | + | ( | 2 | ÷ | 9 | × | a | + | 20 | ) | × | 1 100 | ) | − | 1080000 | ( | a | ÷ | 2 | ) | × | 1 100 |
| = | 840000 | + | 3600 | a | − | 48 | a | a | + | 1080000 | ( | 1 | + | ( | 2 | ÷ | 9 | × | a | + | 20 | ) | × | 1 100 | ) | − | 10800 | ( | a | ÷ | 2 | ) | ( | 1 | + | ( | 2 | ÷ | 9 | × | a | + | 20 | ) | × | 1 100 | ) |
| = | 840000 | + | 3600 | a | − | 48 | a | a | + | 1080000 | × | 1 | + | 1080000 | ( | 2 | ÷ | 9 | × | a | + | 20 | ) | × | 1 100 | − | 10800 |
| = | 840000 | + | 3600 | a | − | 48 | a | a | + | 1080000 | + | 10800 | ( | 2 | ÷ | 9 | × | a | + | 20 | ) | − | 10800 | ( | a | ÷ | 2 | ) | ( | 1 | + | ( | 2 | ÷ | 9 | × | a | + | 20 | ) | × | 1 100 | ) |
| = | 1920000 | + | 3600 | a | − | 48 | a | a | + | 10800 | ( | 2 | ÷ | 9 | × | a | + | 20 | ) | − | 10800 | ( | a | ÷ | 2 | ) | ( | 1 | + | ( | 2 | ÷ | 9 | × | a | + | 20 | ) | × | 1 100 | ) |
| = | 1920000 | + | 3600 | a | − | 48 | a | a | + | 10800 | × | 2 | ÷ | 9 | × | a | + | 10800 | × | 20 |
| = | 1920000 | + | 3600 | a | − | 48 | a | a | + | 2400 | a | + | 216000 | − | 10800 | ( | a | ÷ | 2 | ) | ( | 1 | + | ( | 2 | ÷ | 9 | × | a | + | 20 | ) | × | 1 100 | ) |
| = | 2136000 | + | 6000 | a | − | 48 | a | a | − | 10800 | ( | a | ÷ | 2 | ) | ( | 1 | + | ( | 2 | ÷ | 9 | × | a | + | 20 | ) | × | 1 100 | ) |
| = | 2136000 | + | 6000 | a | − | 48 | a | a | − | 10800 | a | ÷ | 2 | × | ( | 1 | + | ( | 2 | ÷ | 9 | × | a | + | 20 | ) | × | 1 100 | ) |
| = | 2136000 | + | 6000 | a | − | 48 | a | a | − | 5400 | a | ( | 1 | + | ( | 2 | ÷ | 9 | × | a | + | 20 | ) | × | 1 100 | ) |
| = | 2136000 | + | 6000 | a | − | 48 | a | a | − | 5400 | a | × | 1 | − | 5400 | a | ( | 2 | ÷ | 9 | × | a | + | 20 | ) |
| = | 2136000 | + | 6000 | a | − | 48 | a | a | − | 5400 | a | − | 54 | a | ( | 2 | ÷ | 9 | × | a | + | 20 | ) |
| = | 2136000 | + | 600 | a | − | 48 | a | a | − | 54 | a | ( | 2 | ÷ | 9 | × | a | + | 20 | ) |
| = | 2136000 | + | 600 | a | − | 48 | a | a | − | 54 | a | × | 2 | ÷ | 9 | × | a | − | 54 |
| = | 2136000 | + | 600 | a | − | 48 | a | a | − | 12 | a | a | − | 1080 | a |
| = | 2136000 | − | 480 | a | − | 48 | a | a | − | 12 | a | a |