Stage: 3 Challenge Level: 
Take any two digit number, for example 58. What do you have to do to reverse the order of the digits? Can you find a rule for reversing the order of digits for any two digit number? Explain your reasoning.
Place value. Divisibility. Generalising. Number - generally. Visualising. Creating expressions/formulae. Number bases. smartphone. Mathematical reasoning & proof. Factors and multiples.
Published April 1997.
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