| Discovery Type | Historical Relics |
| Discovery Name | black and red arithmetic |
| Rank | ★★★★★(5) (Number of Stars on Discovery Name card) |
| explanation | It was used throughout East Asia before the spread of the abacus. A device for calculating by arranging pieces of wood. In medieval Japan, two-colored arithmetic blocks were used: red to represent positive numbers and black to represent negative numbers. Calculations were made by arranging them on a cloth or board abacus with a grid drawn on it. |
| Era | |
| Deck Points | 7 (Required Deck Points for debate deck) |
| Difficulty | (Rank of skills required for discovery) |
| Experience | (For adventure jobs. Excluding company benefits, beginner bonuses, etc.) |
| Remarks | Legacy Wisdom of Numbers/World Calculator Part 2 |
| 最終更新 | 2020-07-12 22:59:01 Koumeitan |