| 3 | ( | N | × | 129 | × | 1 5 | + | 2000 | ) | = | N | × | 129 | × | 1 5 | + | 2000 |
| Left side of the equation = | 3 | N | × | 129 | × | 1 5 | + | 3 | × | 2000 |
| = | 387 5 | N | + | 6000 |
387 5 | N | + | 6000 | = | N | × | 129 | × | 1 5 | + | 2000 |
| Right side of the equation = | N | × | 129 5 | + | 2000 |
387 5 | N | + | 6000 | = | 129 5 | N | + | 2000 |
387 5 | N | − | 129 5 | N | = | 2000 | − | 6000 |
258 5 | N | = | 2000 | − | 6000 |
258 5 | N | = | - | 4000 |
| N | = | - | 4000 | ÷ | 258 5 |
| = | - | 4000 | × | 5 258 |
| = | - | 2000 | × | 5 129 |
| N | = | - | 10000 129 |
| N | = | - 77.51938 |