| ( | 70 100 | − | 15 100 | ) | − | ( | 1 | + | 10 100 | ) | ÷ | 10 100 | × | 8 100 | ( | 1 | − | x | ) | = | 0 |
| 方程左边 = | ( | 70 100 | − | 15 100 | ) | − | ( | 1 | + | 10 100 | ) | × | 4 5 | ( | 1 | − | x | ) |
| ( | 70 100 | − | 15 100 | ) | − | ( | 1 | + | 10 100 | ) | × | 4 5 | ( | 1 | − | x | ) | = | 0 |
| 方程左边 = | 70 100 | − | 15 100 | − | ( | 1 | + | 10 100 | ) | × | 4 5 | ( | 1 | − | x | ) |
| = | 11 20 | − | ( | 1 | + | 10 100 | ) | × | 4 5 | ( | 1 | − | x | ) |
| = | 11 20 | − | 1 | × | 4 5 | ( | 1 | − | x | ) | − | 10 100 | × | 4 5 | ( | 1 | − | x | ) |
| = | 11 20 | − | 4 5 | ( | 1 | − | x | ) | − | 2 25 | ( | 1 | − | x | ) |
| = | 11 20 | − | 4 5 | × | 1 | + | 4 5 | x | − | 2 25 | ( | 1 | − | x | ) |
| = | 11 20 | − | 4 5 | + | 4 5 | x | − | 2 25 | ( | 1 | − | x | ) |
| = | - | 1 4 | + | 4 5 | x | − | 2 25 | ( | 1 | − | x | ) |
| = | - | 1 4 | + | 4 5 | x | − | 2 25 | × | 1 | + | 2 25 | x |
| = | - | 1 4 | + | 4 5 | x | − | 2 25 | + | 2 25 | x |
| = | - | 33 100 | + | 22 25 | x |
| - | 33 100 | + | 22 25 | x | = | 0 |
22 25 | x | = | 0 | + | 33 100 |
22 25 | x | = | 33 100 |
| x | = | 33 100 | ÷ | 22 25 |
| = | 33 100 | × | 25 22 |
| = | 3 4 | × | 1 2 |
| x | = | 3 8 |
| x | = | 0.375 |