| 169 | × | 20 | − | x | − | 120 | ( | 20 | − | 3 | ) | = | 200 |
| Left side of the equation = | 3380 | − | x | − | 120 | ( | 20 | − | 3 | ) |
| 3380 | − | x | − | 120 | ( | 20 | − | 3 | ) | = | 200 |
| Left side of the equation = | 3380 | − | x | − | 120 | × | 20 | + | 120 | × | 3 |
| = | 3380 | − | x | − | 2400 | + | 360 |
| = | 1340 | − | x |
| 1340 | − | x | = | 200 |
| - | x | = | 200 | − | 1340 |
| - | x | = | - | 1140 |
| 1140 | = | x |
| x | = | 1140 |