| ( | n | − | 1 | ) | ÷ | n | × | ( | n | + | 1 | ) | = | 2381 20000 |
| Multiply both sides of the equation by: | n |
| ( | n | − | 1 | ) | ( | n | + | 1 | ) | = | 2381 20000 | n |
| n | ( | n | + | 1 | ) | − | 1 | ( | n | + | 1 | ) | = | 2381 20000 | n |
| n | n | + | n | × | 1 | − | 1 | ( | n | + | 1 | ) | = | 2381 20000 | n |
| n | n | + | 1 | n | − | 1 | n | − | 1 | × | 1 | = | 2381 20000 | n |
| n | n | + | 1 | n | − | 1 | n | − | 1 | = | 2381 20000 | n |
| n | n | + | 0 | n | − | 1 | = | 2381 20000 | n |