Stage: 3 Challenge Level: 
When asked how old she was, the teacher replied:
My age in years is not prime but oddand when reversed and added to my age
you have a perfect square.
Or you can reverse and subtract, and
again you have a perfect square.
Factors and multiples. Simultaneous equations. Diophantine equations. Number bases. Mathematical reasoning & proof. Place value. Other equations. Divisibility. Properties of numbers. Integers.
Published August 1998.
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