189 25 | + | X | + | ( | ( | X | ÷ | 2 | ÷ | 12 | ) | + | 63 100 | ) | × | 73 200 | × | 12 | = | 21 |
| 方程左边 = | 189 25 | + | X | + | ( | ( | X | ÷ | 2 | ÷ | 12 | ) | + | 63 100 | ) | × | 219 50 |
189 25 | + | X | + | ( | ( | X | ÷ | 2 | ÷ | 12 | ) | + | 63 100 | ) | × | 219 50 | = | 21 |
| 方程左边 = | 189 25 | + | X | + | ( | X | ÷ | 2 | ÷ | 12 | ) | × | 219 50 | + | 63 100 | × | 219 50 |
| = | 189 25 | + | X | + | ( | X | ÷ | 2 | ÷ | 12 | ) | × | 219 50 | + | 13797 5000 |
| = | 51597 5000 | + | X | + | ( | X | ÷ | 2 | ÷ | 12 | ) | × | 219 50 |
| = | 51597 5000 | + | X | + | X | ÷ | 2 | ÷ | 12 | × | 219 50 |
| = | 51597 5000 | + | X | + | X | × | 73 400 |
| = | 51597 5000 | + | 473 400 | X |
51597 5000 | + | 473 400 | X | = | 21 |
473 400 | X | = | 21 | − | 51597 5000 |
473 400 | X | = | 53403 5000 |
| X | = | 53403 5000 | ÷ | 473 400 |
| = | 53403 5000 | × | 400 473 |
| = | 53403 25 | × | 2 473 |
| X | = | 106806 11825 |
| X | = | 9.03222 |