| 100 | + | 4 | x | + | 200 | x | = | ( | 100 | + | 200 | ) | × | 12 100 |
| Left side of the equation = | 100 | + | 204 | x |
| 100 | + | 204 | x | = | ( | 100 | + | 200 | ) | × | 12 100 |
| Right side of the equation = | 100 | × | 12 100 | + | 200 | × | 12 100 |
| = | 12 | + | 24 |
| = | 36 |
| 100 | + | 204 | x | = | 36 |
| 204 | x | = | 36 | − | 100 |
| 204 | x | = | - | 64 |
| x | = | - | 64 | ÷ | 204 |
| = | - | 64 | × | 1 204 |
| = | - | 16 | × | 1 51 |
| x | = | - | 16 51 |
| x | = | - 0.313725 |