| 12 | ( | 1 | − | 10 | ÷ | 3 | × | m | ) | × | 1200 | ( | 1 | + | 6 | m | ) | + | 50 | ( | 1 | − | 4 | m | ) | × | 800 | ( | 1 | − | 4 | m | ) | = | 54400 | − | 80 | m |
| Left side of the equation = | 14400 | ( | 1 | − | 10 | ÷ | 3 | × | m | ) | ( | 1 | + | 6 | m | ) | + | 40000 | ( | 1 | − | 4 | m | ) | ( | 1 | − | 4 | m | ) |
| 14400 | ( | 1 | − | 10 | ÷ | 3 | × | m | ) | ( | 1 | + | 6 | m | ) | + | 40000 | ( | 1 | − | 4 | m | ) | ( | 1 | − | 4 | m | ) | = | 54400 | − | 80 | m |
| Left side of the equation = | 14400 | × | 1 | ( | 1 | + | 6 | m | ) | − | 14400 | × | 10 | ÷ | 3 | × | m | ( | 1 | + | 6 | m | ) | + | 40000 | ( | 1 | − | 4 | m | ) | ( | 1 | − | 4 | m | ) |
| = | 14400 | ( | 1 | + | 6 | m | ) | − | 48000 | m | ( | 1 | + | 6 | m | ) | + | 40000 | ( | 1 | − | 4 | m | ) | ( | 1 | − | 4 | m | ) |
| = | 14400 | × | 1 | + | 14400 | × | 6 | m | − | 48000 | m | ( | 1 | + | 6 | m | ) | + | 40000 | ( | 1 | − | 4 | m | ) | ( | 1 | − | 4 | m | ) |
| = | 14400 | + | 86400 | m | − | 48000 | m | ( | 1 | + | 6 | m | ) | + | 40000 | ( | 1 | − | 4 | m | ) | ( | 1 | − | 4 | m | ) |
| = | 14400 | + | 86400 | m | − | 48000 | m | × | 1 | − | 48000 | m | × | 6 | m | + | 40000 | ( | 1 | − | 4 | m | ) |
| = | 14400 | + | 86400 | m | − | 48000 | m | − | 288000 | m | m | + | 40000 | ( | 1 | − | 4 | m | ) | ( | 1 | − | 4 | m | ) |
| = | 14400 | + | 38400 | m | − | 288000 | m | m | + | 40000 | ( | 1 | − | 4 | m | ) | ( | 1 | − | 4 | m | ) |
| = | 14400 | + | 38400 | m | − | 288000 | m | m | + | 40000 | × | 1 | ( | 1 | − | 4 | m | ) | − | 40000 | × | 4 | m |
| = | 14400 | + | 38400 | m | − | 288000 | m | m | + | 40000 | ( | 1 | − | 4 | m | ) | − | 160000 | m | ( | 1 | − | 4 | m | ) |
| = | 14400 | + | 38400 | m | − | 288000 | m | m | + | 40000 | × | 1 | − | 40000 | × | 4 | m | − | 160000 |
| = | 14400 | + | 38400 | m | − | 288000 | m | m | + | 40000 | − | 160000 | m | − | 160000 | m | ( | 1 | − | 4 | m | ) |
| = | 54400 | − | 121600 | m | − | 288000 | m | m | − | 160000 | m | ( | 1 | − | 4 | m | ) |
| = | 54400 | − | 121600 | m | − | 288000 | m | m | − | 160000 | m | × | 1 | + | 160000 | m | × | 4 |
| = | 54400 | − | 121600 | m | − | 288000 | m | m | − | 160000 | m | + | 640000 | m | m |
| = | 54400 | − | 281600 | m | − | 288000 | m | m | + | 640000 | m | m |
| 54400 | − | 281600 | m | − | 288000 | m | m | + | 640000 | m | m | = | 54400 | − | 80 | m |