| ( | ( | 3000 | − | x | ) | × | 1 4 | + | 150 | ) | ( | 1 | + | 2 | ( | 3000 | − | x | ) | ÷ | 21000 | ) | = | x | − | 1 20 | × | 3000 |
| Left side of the equation = | ( | 3000 | − | x | ) | × | 1 4 | ( | 1 | + | 2 | ( | 3000 | − | x | ) | ÷ | 21000 | ) | + | 150 | ( | 1 | + | 2 | ( | 3000 | − | x | ) | ÷ | 21000 | ) |
| = | 3000 | × | 1 4 | ( | 1 | + | 2 | ( | 3000 | − | x | ) | ÷ | 21000 | ) | − | x | × | 1 4 | ( | 1 | + | 2 | ( | 3000 | − | x | ) | ÷ | 21000 | ) | + | 150 | ( | 1 | + | 2 | ( | 3000 | − | x | ) | ÷ | 21000 | ) |
| = | 750 | ( | 1 | + | 2 | ( | 3000 | − | x | ) | ÷ | 21000 | ) | − | x | × | 1 4 | ( | 1 | + | 2 | ( | 3000 | − | x | ) | ÷ | 21000 | ) | + | 150 | ( | 1 | + | 2 | ( | 3000 | − | x | ) | ÷ | 21000 | ) |
| = | 750 | × | 1 | + | 750 | × | 2 | ( | 3000 | − | x | ) | ÷ | 21000 | − | x | × | 1 4 | ( | 1 | + | 2 | ( | 3000 | − | x | ) | ÷ | 21000 | ) | + | 150 | ( | 1 | + | 2 | ( | 3000 | − | x | ) | ÷ | 21000 | ) |
| = | 750 | + | 1 14 | ( | 3000 | − | x | ) | − | x | × | 1 4 | ( | 1 | + | 2 | ( | 3000 | − | x | ) | ÷ | 21000 | ) | + | 150 | ( | 1 | + | 2 | ( | 3000 | − | x | ) | ÷ | 21000 | ) |
| = | 750 | + | 1 14 | × | 3000 | − | 1 14 | x | − | x | × | 1 4 | ( | 1 | + | 2 | ( | 3000 | − | x | ) | ÷ | 21000 | ) | + | 150 | ( | 1 | + | 2 | ( | 3000 | − | x | ) | ÷ | 21000 | ) |
| = | 750 | + | 1500 7 | − | 1 14 | x | − | x | × | 1 4 | ( | 1 | + | 2 | ( | 3000 | − | x | ) | ÷ | 21000 | ) | + | 150 | ( | 1 | + | 2 | ( | 3000 | − | x | ) | ÷ | 21000 | ) |
| = | 6750 7 | − | 1 14 | x | − | x | × | 1 4 | ( | 1 | + | 2 | ( | 3000 | − | x | ) | ÷ | 21000 | ) | + | 150 | ( | 1 | + | 2 | ( | 3000 | − | x | ) | ÷ | 21000 | ) |
| = | 6750 7 | − | 1 14 | x | − | x | × | 1 4 | × | 1 | − | x | × | 1 4 | × | 2 | ( | 3000 | − | x | ) | ÷ | 21000 | + | 150 |
| = | 6750 7 | − | 1 14 | x | − | x | × | 1 4 | − | x | × | 1 42000 | ( | 3000 | − | x | ) | + | 150 | ( | 1 | + | 2 | ( | 3000 | − | x | ) | ÷ | 21000 | ) |
| = | 6750 7 | − | 9 28 | x | − | x | × | 1 42000 | ( | 3000 | − | x | ) | + | 150 | ( | 1 | + | 2 | ( | 3000 | − | x | ) | ÷ | 21000 | ) |
| = | 6750 7 | − | 9 28 | x | − | x | × | 1 42000 | × | 3000 | + | x | × | 1 42000 | x | + | 150 | ( | 1 | + | 2 | ( | 3000 | − | x | ) | ÷ | 21000 | ) |
| = | 6750 7 | − | 9 28 | x | − | x | × | 1 14 | + | x | × | 1 42000 | x | + | 150 | ( | 1 | + | 2 | ( | 3000 | − | x | ) | ÷ | 21000 | ) |
| = | 6750 7 | − | 11 28 | x | + | x | × | 1 42000 | x | + | 150 | ( | 1 | + | 2 | ( | 3000 | − | x | ) | ÷ | 21000 | ) |
| = | 6750 7 | − | 11 28 | x | + | x | × | 1 42000 | x | + | 150 | × | 1 | + | 150 | × | 2 | ( | 3000 | − | x | ) | ÷ | 21000 |
| = | 6750 7 | − | 11 28 | x | + | x | × | 1 42000 | x | + | 150 | + | 1 70 | ( | 3000 | − | x | ) |
| = | 7800 7 | − | 11 28 | x | + | x | × | 1 42000 | x | + | 1 70 | ( | 3000 | − | x | ) |
| = | 7800 7 | − | 11 28 | x | + | x | × | 1 42000 | x | + | 1 70 | × | 3000 | − | 1 70 | x |
| = | 7800 7 | − | 11 28 | x | + | x | × | 1 42000 | x | + | 300 7 | − | 1 70 | x |
| = | 8100 7 | − | 57 140 | x | + | x | × | 1 42000 | x |
8100 7 | − | 57 140 | x | + | x | × | 1 42000 | x | = | x | − | 1 20 | × | 3000 |
| Right side of the equation = | x | − | 150 |
8100 7 | − | 57 140 | x | + | x | × | 1 42000 | x | = | x | − | 150 |