| x | + | 99 | = | 309 500 | ( | 165 | + | x | ) |
| Right side of the equation = | 309 500 | × | 165 | + | 309 500 | x |
| = | 10197 100 | + | 309 500 | x |
| x | + | 99 | = | 10197 100 | + | 309 500 | x |
| x | − | 309 500 | x | = | 10197 100 | − | 99 |
191 500 | x | = | 10197 100 | − | 99 |
191 500 | x | = | 297 100 |
| x | = | 297 100 | ÷ | 191 500 |
| = | 297 100 | × | 500 191 |
| = | 297 | × | 5 191 |
| x | = | 1485 191 |
| x | = | 7.774869 |