| ( | 31 | − | 30 | ) | ÷ | ( | 30 | − | 22 | ) | = | ( | 55 | − | t | ) | ÷ | ( | t | − | 41 | ) |
| 方程两边同时乘以: | ( | 30 | − | 22 | ) | , | ( | t | − | 41 | ) |
| ( | 31 | − | 30 | ) | ( | t | − | 41 | ) | = | ( | 55 | − | t | ) | ( | 30 | − | 22 | ) |
| 31 | ( | t | − | 41 | ) | − | 30 | ( | t | − | 41 | ) | = | ( | 55 | − | t | ) | ( | 30 | − | 22 | ) |
| 31 | ( | t | − | 41 | ) | − | 30 | ( | t | − | 41 | ) | = | 55 | ( | 30 | − | 22 | ) | − | t | ( | 30 | − | 22 | ) |
| 31 | t | − | 31 | × | 41 | − | 30 | ( | t | − | 41 | ) | = | 55 | ( | 30 | − | 22 | ) | − | t | ( | 30 | − | 22 | ) |
| 31 | t | − | 31 | × | 41 | − | 30 | ( | t | − | 41 | ) | = | 55 | × | 30 | − | 55 | × | 22 | − | t | ( | 30 | − | 22 | ) |
| 31 | t | − | 1271 | − | 30 | ( | t | − | 41 | ) | = | 1650 | − | 1210 | − | t | ( | 30 | − | 22 | ) |
| 31 | t | − | 1271 | − | 30 | ( | t | − | 41 | ) | = | 440 | − | t | ( | 30 | − | 22 | ) |
| 31 | t | − | 1271 | − | 30 | t | + | 30 | × | 41 | = | 440 | − | t | ( | 30 | − | 22 | ) |
| 31 | t | − | 1271 | − | 30 | t | + | 30 | × | 41 | = | 440 | − | t | × | 30 | + | t | × | 22 |
| 31 | t | − | 1271 | − | 30 | t | + | 1230 | = | 440 | − | t | × | 30 | + | t | × | 22 |
| 1 | t | − | 41 | = | 440 | − | 8 | t |
| 1 | t | + | 8 | t | = | 440 | + | 41 |
| 9 | t | = | 440 | + | 41 |
| 9 | t | = | 481 |
| t | = | 481 | ÷ | 9 |
| = | 481 | × | 1 9 |
| t | = | 481 9 |
| t | = | 53.444444 |