| ( | 500 | + | 5 | m | ) | ( | 100 | + | m | ÷ | 2 | ) | = | 66 |
| Left side of the equation = | 500 | ( | 100 | + | m | ÷ | 2 | ) | + | 5 | m | ( | 100 | + | m | ÷ | 2 | ) |
| = | 500 | × | 100 | + | 500 | m | ÷ | 2 | + | 5 | m | ( | 100 | + | m | ÷ | 2 | ) |
| = | 50000 | + | 250 | m | + | 5 | m | ( | 100 | + | m | ÷ | 2 | ) |
| = | 50000 | + | 250 | m | + | 5 | m | × | 100 | + | 5 | m | m | ÷ | 2 |
| = | 50000 | + | 250 | m | + | 500 | m | + | 5 2 | m | m |
| = | 50000 | + | 750 | m | + | 5 2 | m | m |
| 50000 | + | 750 | m | + | 5 2 | m | m | = | 66 |