| 4000 | ÷ | x | = | 4000 | ÷ | ( | 13 10 | x | ) | + | 7 |
| Multiply both sides of the equation by: | x | , | ( | 13 10 | × | 1 | ) |
| 4000 | ( | 13 10 | × | 1 | ) | = | 4000 | × | 1 | + | 7 | x | ( | 13 10 | × | 1 | ) |
| 4000 | × | 13 10 | × | 1 | = | 4000 | × | 1 | + | 7 | x | ( | 13 10 | × | 1 | ) |
| 4000 | × | 13 10 | × | 1 | = | 4000 | × | 1 | + | 7 | x | × | 13 10 | × | 1 |
| 5200 | = | 4000 | + | 91 10 | x |
| - | 91 10 | x | = | 4000 | − | 5200 |
| - | 91 10 | x | = | - | 1200 |
| 1200 | = | 91 10 | x |
91 10 | x | = | 1200 |
| x | = | 1200 | ÷ | 91 10 |
| = | 1200 | × | 10 91 |
| x | = | 12000 91 |
| x | = | 131.868132 |