Stage: 5 Challenge Level: 
This can be solved by just working systematically with the information, thinking about which numbers are divisible by 4 and 3, and testing the possibilities.
Modulus arithmetic also provides an efficient way to solve the problem.
Modulus arithmetic. Creating expressions/formulae. epsilons. Index notation/Indices. Factors and multiples. Mathematical reasoning & proof. Other equations. alphas. Manipulating algebraic expressions/formulae. Stage 5 - Reviewed 2012.
Published October 1999.
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