| X | ÷ | 200 | = | X | + | 3 5 | ÷ | 200 | × | 4 |
| Right side of the equation = | X | + | 3 250 |
1 200 | X | = | X | + | 3 250 |
1 200 | X | − | X | = | 3 250 |
| - | 199 200 | X | = | 3 250 |
| - | 3 250 | = | 199 200 | X |
199 200 | X | = | - | 3 250 |
| X | = | - | 3 250 | ÷ | 199 200 |
| = | - | 3 250 | × | 200 199 |
| = | - | 3 5 | × | 4 199 |
| X | = | - | 12 995 |
| X | = | - 0.01206 |