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Primary Krypto

Pre-K-2, 3-5, 6-8
Number and Operations
Math Content:
Number and Operations

The rules of Krypto are simple: Combine five number cards using the four arithmetic operations (+, –, ×, ÷) to arrive at a "target" number. This online version of Primary Krypto uses the numbers 1–10 only.

  • Drag-and-drop the number cards onto the game board. They will snap into place on the outlined squares. From the small squares, choose which operation is to be performed.
  • The three buttons are used to control the game:
    • deal - get a new set of number cards and a new target number
    • hint - for the current hand, reveal one possible set of operations that yield a solution
    • solve - see our solution (though not necessarily the only solution)
    • Click deal to generate a set of number cards and a target number. Find a solution for the puzzle. Then, click the hint button if you did not find our solution. Can you find a solution that uses the operations in the order supplied by the hint?
    • What problem-solving strategies can be used while playing Primary Krypto?