| x | ÷ | ( | 100 | + | x | ) | = | 21 1000 |
| Multiply both sides of the equation by: | ( | 100 | + | x | ) |
| x | = | 21 1000 | ( | 100 | + | x | ) |
| x | = | 21 1000 | × | 100 | + | 21 1000 | x |
| x | = | 21 10 | + | 21 1000 | x |
| x | − | 21 1000 | x | = | 21 10 |
979 1000 | x | = | 21 10 |
| x | = | 21 10 | ÷ | 979 1000 |
| = | 21 10 | × | 1000 979 |
| = | 21 | × | 100 979 |
| x | = | 2100 979 |
| x | = | 2.145046 |