| x | × | 15 100 | + | ( | 70 100 | − | x% | ) | × | 12 100 | + | 30 100 | × | 10 100 | = | 13 100 |
| 方程左边 = | x | × | 15 100 | + | ( | 70 100 | − | x% | ) | × | 12 100 | + | 3 100 |
15 100 | x | + | ( | 70 100 | − | x% | ) | × | 12 100 | + | 3 100 | = | 13 100 |
| 方程左边 = | 15 100 | x | + | 70 100 | × | 12 100 | − | x% | × | 12 100 | + | 3 100 |
| = | 15 100 | x | + | 21 250 | − | 3 2500 | x | + | 3 100 |
| = | 15 100 | x | + | 57 500 | − | 3 2500 | x |
15 100 | x | + | 57 500 | − | 3 2500 | x | = | 13 100 |
15 100 | x | − | 3 2500 | x | = | 13 100 | − | 57 500 |
93 625 | x | = | 13 100 | − | 57 500 |
93 625 | x | = | 2 125 |
| x | = | 2 125 | ÷ | 93 625 |
| = | 2 125 | × | 625 93 |
| = | 2 | × | 5 93 |
| x | = | 10 93 |
| x | = | 0.107527 |