| ( | n | − | 4 | ) | ÷ | ( | n | + | 1 | ) | = | 11 25 |
| 方程两边同时乘以: | ( | n | + | 1 | ) |
| ( | n | − | 4 | ) | = | 11 25 | ( | n | + | 1 | ) |
| n | − | 4 | = | 11 25 | ( | n | + | 1 | ) |
| n | − | 4 | = | 11 25 | n | + | 11 25 | × | 1 |
| n | − | 4 | = | 11 25 | n | + | 11 25 |
| n | − | 11 25 | n | = | 11 25 | + | 4 |
14 25 | n | = | 11 25 | + | 4 |
14 25 | n | = | 111 25 |
| n | = | 111 25 | ÷ | 14 25 |
| = | 111 25 | × | 25 14 |
| = | 111 | × | 1 14 |
| n | = | 111 14 |
| n | = | 7.928571 |