| 100 | × | 50 | + | 5 100 | x | = | 15 100 | × | 100 | + | 15 100 | x |
| Left side of the equation = | 5000 | + | 5 100 | x |
| 5000 | + | 5 100 | x | = | 15 100 | × | 100 | + | 15 100 | x |
| Right side of the equation = | 15 | + | 15 100 | x |
| 5000 | + | 5 100 | x | = | 15 | + | 15 100 | x |
5 100 | x | − | 15 100 | x | = | 15 | − | 5000 |
| - | 1 10 | x | = | 15 | − | 5000 |
| - | 1 10 | x | = | - | 4985 |
| 4985 | = | 1 10 | x |
1 10 | x | = | 4985 |
| x | = | 4985 | ÷ | 1 10 |
| = | 4985 | × | 10 |
| x | = | 49850 |