309 500 | ( | 180 | − | n | ) | = | n |
方程左边 = | 309 500 | × | 180 | − | 309 500 | n |
= | 2781 25 | − | 309 500 | n |
2781 25 | − | 309 500 | n | = | n |
- | 309 500 | n | − | n | = | - | 2781 25 |
- | 809 500 | n | = | - | 2781 25 |
2781 25 | = | 809 500 | n |
809 500 | n | = | 2781 25 |
n | = | 2781 25 | ÷ | 809 500 |
= | 2781 25 | × | 500 809 |
= | 2781 | × | 20 809 |
n | = | 55620 809 |
n | = | 68.751545 |