| ( | 20 | − | a | ) | ÷ | 3 | = | ( | 26 | − | a | ) | ÷ | 5 |
| Left side of the equation = | 20 | × | 1 3 | − | a | × | 1 3 |
| = | 20 3 | − | a | × | 1 3 |
20 3 | − | 1 3 | a | = | ( | 26 | − | a | ) | ÷ | 5 |
| Right side of the equation = | 26 | × | 1 5 | − | a | × | 1 5 |
| = | 26 5 | − | a | × | 1 5 |
20 3 | − | 1 3 | a | = | 26 5 | − | 1 5 | a |
| - | 1 3 | a | + | 1 5 | a | = | 26 5 | − | 20 3 |
| - | 2 15 | a | = | 26 5 | − | 20 3 |
| - | 2 15 | a | = | - | 22 15 |
22 15 | = | 2 15 | a |
2 15 | a | = | 22 15 |
| a | = | 22 15 | ÷ | 2 15 |
| = | 22 15 | × | 15 2 |
| = | 11 | × | 1 |
| a | = | 11 |