







What is the sum of the numbers missing from this Sudoku puzzle?
Topics: Starter  Arithmetic  Multiple Intelligences  Puzzles
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The sum of the missing numbers is 73
You did not need to complete the sudoku puzzle to find this answer. The completed puzzle could look like this (though there might be other solutions).








Note to teacher: Doing this activity once with a class helps students develop strategies. It is only when they do this activity a second time that they will have the opportunity to practise those strategies. That is when the learning is consolidated. Click the button above to regenerate another version of this starter from random numbers.
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Teacher, do your students have
access to computers? 

Here a concise URL for a version of this page without the comments.
Here is the URL which will take them to an interactive Sudoku activity.
Here is the URL which will take them to similar number puzzles called Suko and Sujiko.