| 30000 | × | 110 | + | 20000 | y | = | 13 10 | × | 30000 | × | 80 | + | 13 10 | × | 20000 | × | 100 |
| Left side of the equation = | 3300000 | + | 20000 | y |
| 3300000 | + | 20000 | y | = | 13 10 | × | 30000 | × | 80 | + | 13 10 | × | 20000 | × | 100 |
| Right side of the equation = | 3120000 | + | 2600000 |
| = | 5720000 |
| 3300000 | + | 20000 | y | = | 5720000 |
| 20000 | y | = | 5720000 | − | 3300000 |
| 20000 | y | = | 2420000 |
| y | = | 2420000 | ÷ | 20000 |
| = | 2420000 | × | 1 20000 |
| = | 121 | × | 1 |
| y | = | 121 |