| 30000 | × | 110 | + | 20000 | x | − | ( | 30000 | × | 80 | + | 20000 | × | 100 | ) | = | ( | 30000 | × | 80 | + | 20000 | × | 100 | ) | × | 3 10 |
| Left side of the equation = | 3300000 | + | 20000 | x | − | ( | 30000 | × | 80 | + | 20000 | × | 100 | ) |
| 3300000 | + | 20000 | x | − | ( | 30000 | × | 80 | + | 20000 | × | 100 | ) | = | ( | 30000 | × | 80 | + | 20000 | × | 100 | ) | × | 3 10 |
| Left side of the equation = | 3300000 | + | 20000 | x | − | 30000 | × | 80 | − | 20000 | × | 100 |
| = | 3300000 | + | 20000 | x | − | 2400000 | − | 2000000 |
| = | - | 1100000 | + | 20000 | x |
| - | 1100000 | + | 20000 | x | = | ( | 30000 | × | 80 | + | 20000 | × | 100 | ) | × | 3 10 |
| Right side of the equation = | 30000 | × | 80 | × | 3 10 | + | 20000 | × | 100 | × | 3 10 |
| = | 720000 | + | 600000 |
| = | 1320000 |
| - | 1100000 | + | 20000 | x | = | 1320000 |
| 20000 | x | = | 1320000 | + | 1100000 |
| 20000 | x | = | 2420000 |
| x | = | 2420000 | ÷ | 20000 |
| = | 2420000 | × | 1 20000 |
| = | 121 | × | 1 |
| x | = | 121 |