123 1250 | X | + | 160 | + | 35 | × | 12 | = | 11 1000 | X | + | 200 | + | 25 | × | 12 |
| Left side of the equation = | 123 1250 | X | + | 160 | + | 420 |
| = | 123 1250 | X | + | 580 |
123 1250 | X | + | 580 | = | 11 1000 | X | + | 200 | + | 25 | × | 12 |
| Right side of the equation = | 11 1000 | X | + | 200 | + | 300 |
| = | 11 1000 | X | + | 500 |
123 1250 | X | + | 580 | = | 11 1000 | X | + | 500 |
123 1250 | X | − | 11 1000 | X | = | 500 | − | 580 |
437 5000 | X | = | 500 | − | 580 |
437 5000 | X | = | - | 80 |
| X | = | - | 80 | ÷ | 437 5000 |
| = | - | 80 | × | 5000 437 |
| X | = | - | 400000 437 |
| X | = | - 915.331808 |