| ( | 396 | + | x | ) | ÷ | ( | 3507 | + | x | ) | = | 3 25 |
| Multiply both sides of the equation by: | ( | 3507 | + | x | ) |
| ( | 396 | + | x | ) | = | 3 25 | ( | 3507 | + | x | ) |
| 396 | + | x | = | 3 25 | ( | 3507 | + | x | ) |
| 396 | + | x | = | 3 25 | × | 3507 | + | 3 25 | x |
| 396 | + | x | = | 10521 25 | + | 3 25 | x |
| x | − | 3 25 | x | = | 10521 25 | − | 396 |
22 25 | x | = | 10521 25 | − | 396 |
22 25 | x | = | 621 25 |
| x | = | 621 25 | ÷ | 22 25 |
| = | 621 25 | × | 25 22 |
| = | 621 | × | 1 22 |
| x | = | 621 22 |
| x | = | 28.227273 |