| 1 | ÷ | 6 | + | ( | 1 | ÷ | 60 | + | 1 | ÷ | 90 | ) | X | = | 1 |
| Left side of the equation = | 1 6 | + | ( | 1 | ÷ | 60 | + | 1 | ÷ | 90 | ) | X |
1 6 | + | ( | 1 | ÷ | 60 | + | 1 | ÷ | 90 | ) | X | = | 1 |
| Left side of the equation = | 1 6 | + | 1 | ÷ | 60 | × | X | + | 1 | ÷ | 90 | × | X |
| = | 1 6 | + | 1 60 | X | + | 1 90 | X |
| = | 1 6 | + | 1 36 | X |
1 6 | + | 1 36 | X | = | 1 |
1 36 | X | = | 1 | − | 1 6 |
1 36 | X | = | 5 6 |
| X | = | 5 6 | ÷ | 1 36 |
| = | 5 6 | × | 36 |
| = | 5 | × | 6 |
| X | = | 30 |