x% | × | 15 100 | + | ( | 70 100 | − | x% | ) | × | 20 100 | + | 30 100 | × | 10 100 | = | 13 100 |
方程左边 = | 3 2000 | x | + | ( | 70 100 | − | x% | ) | × | 20 100 | + | 3 100 |
3 2000 | x | + | ( | 70 100 | − | x% | ) | × | 20 100 | + | 3 100 | = | 13 100 |
方程左边 = | 3 2000 | x | + | 70 100 | × | 20 100 | − | x% | × | 20 100 | + | 3 100 |
= | 3 2000 | x | + | 7 50 | − | x 500 | + | 3 100 |
= | 3 2000 | x | + | 17 100 | − | x 500 |
3 2000 | x | + | 17 100 | − | x 500 | = | 13 100 |
3 2000 | x | − | x 500 | = | 13 100 | − | 17 100 |
- | 1 2000 | x | = | 13 100 | − | 17 100 |
- | 1 2000 | x | = | - | 1 25 |
1 25 | = | 1 2000 | x |
1 2000 | x | = | 1 25 |
x | = | 1 25 | ÷ | 1 2000 |
= | 1 25 | × | 2000 |
= | 1 | × | 80 |
x | = | 80 |