Stage: 4 Challenge Level: 
111, 222, 333,... etc are all divisible by 37.
A second hint is to use 1000= 999+1 when breaking the number into blocks of 3 digits
Number - generally. Place value. Mathematical reasoning & proof. Modulus arithmetic. Binomial Theorem. Factorisation (algebraic). Index notation/Indices. Factors and multiples. Number bases. Divisibility.
Published March 1999.
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