77 10 | + | ( | 15 | × | 77 10 | ) | = | 77 10 | + | 2 5 | X |
| Left side of the equation = | 77 10 | + | 15 | × | 77 10 |
| = | 77 10 | + | 231 2 |
| = | 616 5 |
616 5 | = | 77 10 | + | 2 5 | X |
| - | 2 5 | X | = | 77 10 | − | 616 5 |
| - | 2 5 | X | = | - | 231 2 |
231 2 | = | 2 5 | X |
2 5 | X | = | 231 2 |
| X | = | 231 2 | ÷ | 2 5 |
| = | 231 2 | × | 5 2 |
| X | = | 1155 4 |
| X | = | 288.75 |