| 9000 | × | 18 | m | + | 500 | ( | 60 | − | m | ) | = | 39000 | + | 9000 |
| Left side of the equation = | 162000 | m | + | 500 | ( | 60 | − | m | ) |
| 162000 | m | + | 500 | ( | 60 | − | m | ) | = | 39000 | + | 9000 |
| Left side of the equation = | 162000 | m | + | 500 | × | 60 | − | 500 | m |
| = | 162000 | m | + | 30000 | − | 500 | m |
| = | 161500 | m | + | 30000 |
| 161500 | m | + | 30000 | = | 39000 | + | 9000 |
| Right side of the equation = | 48000 |
| 161500 | m | + | 30000 | = | 48000 |
| 161500 | m | = | 48000 | − | 30000 |
| 161500 | m | = | 18000 |
| m | = | 18000 | ÷ | 161500 |
| = | 18000 | × | 1 161500 |
| = | 36 | × | 1 323 |
| m | = | 36 323 |
| m | = | 0.111455 |