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Which rational numbers cannot be written in the form x + 1/(y + 1/z) where x, y and z are integers?
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Age 14 to 16 Short Challenge Level:
In each row of the table, the third cell contains the sum of the contents of the first two cells.
In each column of the table, the third cell contains the sum of the contents of the first two cells.
This problem is adapted from the World Mathematics Championships
What total would you get if you added up the contents of all nine cells?
This problem is adapted from the World Mathematics Championships
You can find more short problems, arranged by curriculum topic, in our short problems collection.
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NRICH is part of the family of activities in the Millennium Mathematics Project.
NRICH is part of the family of activities in the Millennium Mathematics Project.