| 120 | ( | 10000 | ÷ | x | ) | + | 130 | ( | 10000 | ÷ | 120 | − | 10000 | ÷ | x | ) | + | 60 | ( | 10000 | ÷ | x | ) | + | 80 | ( | 20000 | ÷ | x | − | 10000 | ÷ | 60 | ) | + | 100 | ( | 10000 | ÷ | x | ) | = | 20000 |
| 120 | × | 10000 | ÷ | x | + | 130 | ( | 10000 | ÷ | 120 | − | 10000 | ÷ | x | ) | + | 60 | ( | 10000 | ÷ | x | ) | + | 80 | ( | 20000 | ÷ | x | − | 10000 | ÷ | 60 | ) | + | 100 | ( | 10000 | ÷ | x | ) | = | 20000 |
| 1200000 | ÷ | x | + | 130 | ( | 10000 | ÷ | 120 | − | 10000 | ÷ | x | ) | + | 60 | ( | 10000 | ÷ | x | ) | + | 80 | ( | 20000 | ÷ | x | − | 10000 | ÷ | 60 | ) | + | 100 | ( | 10000 | ÷ | x | ) | = | 20000 |
| Multiply both sides of the equation by: | x |
| 1200000 | + | 130 | ( | 10000 | ÷ | 120 | − | 10000 | ÷ | x | ) | x | + | 60 | ( | 10000 | ÷ | 1 | ) | × | 1 | + | 80 | ( | 20000 | ÷ | x | − | 10000 | ÷ | 60 | ) | x | + | 100 | ( | 10000 | ÷ | 1 | ) | = | 20000 | x |
| 1200000 | + | 130 | × | 10000 | ÷ | 120 | × | x | − | 130 | × | 10000 | ÷ | x | × | x | + | 60 | ( | 10000 | ÷ | 1 | ) | × | 1 | = | 20000 | x |
| 1200000 | + | 32500 3 | x | − | 1300000 | ÷ | x | × | x | + | 60 | ( | 10000 | ÷ | 1 | ) | + | 80 | ( | 20000 | ÷ | x | − | 10000 | ÷ | 60 | ) | x | + | 100 | = | 20000 | x |
| 1200000 | + | 32500 3 | x | − | 1300000 | ÷ | 1 | × | 1 | + | 60 | × | 10000 | ÷ | 1 | + | 80 | ( | 20000 | ÷ | x | − | 10000 | ÷ | 60 | ) | x | = | 20000 | x |
| 1200000 | + | 32500 3 | x | − | 1300000 | + | 600000 | + | 80 | ( | 20000 | ÷ | x | − | 10000 | ÷ | 60 | ) | x | + | 100 | ( | 10000 | ÷ | 1 | ) | = | 20000 | x |
| 500000 | + | 32500 3 | x | + | 80 | ( | 20000 | ÷ | x | − | 10000 | ÷ | 60 | ) | x | + | 100 | ( | 10000 | ÷ | 1 | ) | = | 20000 | x |
| 500000 | + | 32500 3 | x | + | 80 | × | 20000 | ÷ | x | × | x | − | 80 | × | 10000 | ÷ | 60 | × | x | + | 100 | = | 20000 | x |
| 500000 | + | 32500 3 | x | + | 1600000 | ÷ | x | × | x | − | 40000 3 | x | + | 100 | ( | 10000 | ÷ | 1 | ) | = | 20000 | x |
| 500000 | − | 2500 | x | + | 1600000 | ÷ | x | × | x | + | 100 | ( | 10000 | ÷ | 1 | ) | = | 20000 | x |
| 500000 | − | 2500 | x | + | 1600000 | ÷ | 1 | × | 1 | + | 100 | × | 10000 | ÷ | 1 | = | 20000 | x |
| 500000 | − | 2500 | x | + | 1600000 | + | 1000000 | = | 20000 | x |
| 3100000 | − | 2500 | x | = | 20000 | x |
| - | 2500 | x | − | 20000 | x | = | - | 3100000 |
| - | 22500 | x | = | - | 3100000 |
| 3100000 | = | 22500 | x |
| 22500 | x | = | 3100000 |
| x | = | 3100000 | ÷ | 22500 |
| = | 3100000 | × | 1 22500 |
| = | 1240 | × | 1 9 |
| x | = | 1240 9 |
| x | = | 137.777778 |