| ( | m | ÷ | 2 | + | 40 | ) | ÷ | 10 | × | m | = | ( | m | ÷ | 2 | − | 40 | ) | ÷ | 15 | × | m |
| Left side of the equation = | m | ÷ | 2 | × | 1 10 | m | + | 40 | × | 1 10 | m |
| = | m | × | 1 20 | m | + | 4 | m |
| m | × | 1 20 | m | + | 4 | m | = | ( | m | ÷ | 2 | − | 40 | ) | ÷ | 15 | × | m |
| Right side of the equation = | m | ÷ | 2 | × | 1 15 | m | − | 40 | × | 1 15 | m |
| = | m | × | 1 30 | m | − | 8 3 | m |
| m | × | 1 20 | m | + | 4 | m | = | m | × | 1 30 | m | − | 8 3 | m |