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If n and k are positive integers, is n divisible by 6? (1) n = k(k + 1)(k - 1) (2) k – 1 is a multiple of 3.
St.1: Insuf. b/c K=???
St.2: Insuf.- nothing about N????
k-1 is a mult. of 3-->( k^2-1) is a mult of 3.
k=10 n=10x(100-1)=10x99=990 -->990/3=330