80 | y | − | 15 | ( | 6750 | − | 25 | y | ) | ÷ | 120 | = | 550 |
方程左边 = | 80 | y | − | 1 8 | ( | 6750 | − | 25 | y | ) |
80 | y | − | 1 8 | ( | 6750 | − | 25 | y | ) | = | 550 |
方程左边 = | 80 | y | − | 1 8 | × | 6750 | + | 1 8 | × | 25 | y |
= | 80 | y | − | 3375 4 | + | 25 8 | y |
= | 665 8 | y | − | 3375 4 |
665 8 | y | − | 3375 4 | = | 550 |
665 8 | y | = | 550 | + | 3375 4 |
665 8 | y | = | 5575 4 |
y | = | 5575 4 | ÷ | 665 8 |
= | 5575 4 | × | 8 665 |
= | 1115 | × | 2 133 |
y | = | 2230 133 |
y | = | 16.766917 |