| 30000 | × | 110 | + | 20000 | x | − | 30000 | × | 80 | + | 20000 | × | 100 | = | ( | 30000 | × | 80 | + | 20000 | × | 100 | ) | × | 3 10 |
| Left side of the equation = | 3300000 | + | 20000 | x | − | 2400000 | + | 2000000 |
| = | 2900000 | + | 20000 | x |
| 2900000 | + | 20000 | x | = | ( | 30000 | × | 80 | + | 20000 | × | 100 | ) | × | 3 10 |
| Right side of the equation = | 30000 | × | 80 | × | 3 10 | + | 20000 | × | 100 | × | 3 10 |
| = | 720000 | + | 600000 |
| = | 1320000 |
| 2900000 | + | 20000 | x | = | 1320000 |
| 20000 | x | = | 1320000 | − | 2900000 |
| 20000 | x | = | - | 1580000 |
| x | = | - | 1580000 | ÷ | 20000 |
| = | - | 1580000 | × | 1 20000 |
| = | - | 79 | × | 1 |
| x | = | - | 79 |