Stage: 2 Challenge Level: 
Charlie's house number is a square of 3 digits. This number when reversed is also a square and is Charlie's telephone extension at work. His car registration number is a square of 4 digits and is formed from his house number by repeating the right hand digit.
What is Charlie's house number?
Working systematically. Interactivities. Visualising. Combinations. Investigations. Factors and multiples. Square numbers. Practical Activity. Multiplication & division. Addition & subtraction.
Published October 2002.
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