Stage: 4 Challenge Level: 
115 2 = (11 x 12)25
that is 13225
895 2 = (89 x 90)25
that is 801025
Can you explain what is happening and generalise?
Properties of numbers. Factors and multiples. Number theory. Index notation/Indices. Mathematical reasoning & proof. Number bases. Place value. Working systematically. Manipulating algebraic expressions/formulae. Modulus arithmetic.
Published September 2002.
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