| 4200 | ( | X | ÷ | 126 | − | 1 20 | − | 8 | ÷ | 277 | ) | = | 14 5 | ( | 80 | + | X | ) |
| Left side of the equation = | 4200 | X | ÷ | 126 | − | 4200 | × | 1 20 | − | 4200 | × | 8 | ÷ | 277 |
| = | 100 3 | X | − | 210 | − | 33600 277 |
| = | 100 3 | X | − | 91770 277 |
100 3 | X | − | 91770 277 | = | 14 5 | ( | 80 | + | X | ) |
| Right side of the equation = | 14 5 | × | 80 | + | 14 5 | X |
| = | 224 | + | 14 5 | X |
100 3 | X | − | 91770 277 | = | 224 | + | 14 5 | X |
100 3 | X | − | 14 5 | X | = | 224 | + | 91770 277 |
458 15 | X | = | 224 | + | 91770 277 |
458 15 | X | = | 153818 277 |
| X | = | 153818 277 | ÷ | 458 15 |
| = | 153818 277 | × | 15 458 |
| = | 76909 277 | × | 15 229 |
| X | = | 1153635 63433 |
| X | = | 18.186669 |