Stage: 3 Challenge Level: 
Look carefully at the sum below:
[3(230 + A)] 2 = 492 80A
What is the value of the digit A and HOW did you arrive at your answer?
Workshop. Factors and multiples. Mathematical reasoning & proof. Divisibility. Properties of numbers. Multiplication & division. Modulus arithmetic. Working systematically. smartphone. Square numbers.
Published January 1999.
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