The Subtraction Game - Instructions and Help

The Subtraction Game is based on a widely used method of subtraction; this method uses the concept of borrowing and a system of markings called crutches. Wikipedia has a description of this method.

How to play the game

General Instructions
Game Boxes for Input
Game Essentials

User Interface Elements

  • In the right pane of the Game Panel above, you see (from top to bottom):
    • Four or more rows, containing digits or Boxes:
      • The top row of Boxes is for borrows during subtraction.
      • The next row contains the number from which you will be subtracting. You can click on the digits of this number to borrow during subtraction
      • The next row contains the number to be subtracted.
      • The bottom row of Boxes is for the results of the subtraction.
    • A Green Status Box - that gives you helpful real-time information as you play the game.
  • In the center and bottom of the left pane, you see:
    • A 'New Question' Button to generate a new Subtraction problem.
    • A 'Reset Parameters' Button to reset the game parameters (Difficulty-Level, Time-Limit, and other game-specific parameters) to their values at the start of the current Question. This button is disabled to begin with. It becomes enabled as soon as you change a game parameter.
    • A Stop-watch that tells you how much time you have taken on the current problem.
    • A Score-card that tells you your score for the current session. The Score-card reports your grades and scores separately for the different question difficulty levels: 1 - Easy, 2 - Middling, 3- Hard.
    • A Clear Score button to reset the Score-card.
    • A Print Score For button that prints out the Score-card. You can optionally provide a name to be printed on the Score-card page.
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