2430 | ÷ | ( | 10 | × | x% | ) | − | 3240 | ÷ | ( | 15 | × | x% | ) | = | 30 |
方程两边同时乘以: | ( | 10 | × | x% | ) |
2430 | − | 3240 | ÷ | ( | 15 | × | 1 100 | ) | × | ( | 10 | × | 1 100 | ) | = | 30 | ( | 10 | × | x% | ) |
2430 | − | 3240 | ÷ | ( | 15 | × | 1 100 | ) | × | 10 | × | 1 100 | = | 30 | ( | 10 | × | x% | ) |
2430 | − | 3240 | ÷ | ( | 15 | × | 1 100 | ) | × | 10 | × | 1 100 | = | 30 | × | 10 | × | x% |
2430 | − | 324 | ÷ | ( | 15 | × | 1 100 | ) | = | 3 | x |
方程两边同时乘以: | ( | 15 | × | 1 100 | ) |
2430 | ( | 15 | × | 1 100 | ) | − | 324 | = | 3 | x | ( | 15 | × | 1 100 | ) |
2430 | × | 15 | × | 1 100 | − | 324 | = | 3 | x | ( | 15 | × | 1 100 | ) |
2430 | × | 15 | × | 1 100 | − | 324 | = | 3 | x | × | 15 | × | 1 100 |
729 2 | − | 324 | = | 9 20 | x |
81 2 | = | 9 20 | x |
9 20 | x | = | 81 2 |
x | = | 81 2 | ÷ | 9 20 |
= | 81 2 | × | 20 9 |
= | 9 | × | 10 |
x | = | 90 |