1 5 | = | ( | 30 | × | 3 20 | + | 50 | x | ) | ÷ | 80 |
| Right side of the equation = | 30 | × | 3 20 | × | 1 80 | + | 50 | x | × | 1 80 |
| = | 9 160 | + | 5 8 | x |
1 5 | = | 9 160 | + | 5 8 | x |
| - | 5 8 | x | = | 9 160 | − | 1 5 |
| - | 5 8 | x | = | - | 23 160 |
23 160 | = | 5 8 | x |
5 8 | x | = | 23 160 |
| x | = | 23 160 | ÷ | 5 8 |
| = | 23 160 | × | 8 5 |
| = | 23 20 | × | 1 5 |
| x | = | 23 100 |
| x | = | 0.23 |