| 100 | − | 10 | t | − | ( | ( | 10 | − | 2 | t | ) | t | ) | ÷ | 2 | − | ( | 10 | − | t | ) | × | 5 | = | 25 |
| Left side of the equation = | 100 | − | 10 | t | − | ( | 10 | − | 2 | t | ) | t | × | 1 2 | − | ( | 10 | − | t | ) | × | 5 |
| = | 100 | − | 10 | t | − | 10 | t | × | 1 2 | + | 2 | t | t | × | 1 2 | − | ( | 10 | − | t | ) | × | 5 |
| = | 100 | − | 10 | t | − | 5 | t | + | 1 | t | t | − | ( | 10 | − | t | ) | × | 5 |
| = | 100 | − | 15 | t | + | 1 | t | t | − | ( | 10 | − | t | ) | × | 5 |
| = | 100 | − | 15 | t | + | 1 | t | t | − | 10 | × | 5 | + | t | × | 5 |
| = | 100 | − | 15 | t | + | 1 | t | t | − | 50 | + | t | × | 5 |
| = | 50 | − | 10 | t | + | 1 | t | t |
| 50 | − | 10 | t | + | 1 | t | t | = | 25 |