| 100 | ( | 1 | + | x | ) | × | 2 | + | 200 | ( | 1 | + | x | ) | + | 300 | = | 500 | ( | 1 | + | x | ) | × | 3 |
| 方程左边 = | 200 | ( | 1 | + | x | ) | + | 200 | ( | 1 | + | x | ) | + | 300 |
| 200 | ( | 1 | + | x | ) | + | 200 | ( | 1 | + | x | ) | + | 300 | = | 500 | ( | 1 | + | x | ) | × | 3 |
| 方程左边 = | 200 | × | 1 | + | 200 | x | + | 200 | ( | 1 | + | x | ) | + | 300 |
| = | 200 | + | 200 | x | + | 200 | ( | 1 | + | x | ) | + | 300 |
| = | 500 | + | 200 | x | + | 200 | ( | 1 | + | x | ) |
| = | 500 | + | 200 | x | + | 200 | × | 1 | + | 200 | x |
| = | 500 | + | 200 | x | + | 200 | + | 200 | x |
| = | 700 | + | 400 | x |
| 700 | + | 400 | x | = | 500 | ( | 1 | + | x | ) | × | 3 |
| 方程右边 = | 1500 | ( | 1 | + | x | ) |
| 700 | + | 400 | x | = | 1500 | ( | 1 | + | x | ) |
| 方程右边 = | 1500 | × | 1 | + | 1500 | x |
| = | 1500 | + | 1500 | x |
| 700 | + | 400 | x | = | 1500 | + | 1500 | x |
| 400 | x | − | 1500 | x | = | 1500 | − | 700 |
| - | 1100 | x | = | 1500 | − | 700 |
| - | 1100 | x | = | 800 |
| - | 800 | = | 1100 | x |
| 1100 | x | = | - | 800 |
| x | = | - | 800 | ÷ | 1100 |
| = | - | 800 | × | 1 1100 |
| = | - | 8 | × | 1 11 |
| x | = | - | 8 11 |
| x | = | - 0.727273 |