Questions about the world of GMAT Math from other sources and general math related questions.
cutlass
 
 

Is(n-1)n(n+1) divisible by 3 for any int 'n', including n=1?

by cutlass Mon May 05, 2008 12:49 am

Vinod
 
 

by Vinod Mon May 05, 2008 2:22 am

Consecutive numbers say 3*4*5 are divisible by the number of terms in the series i.e.3 in this case.

Take 21*22*23*24 is divisible by 4.
RonPurewal
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by RonPurewal Mon May 05, 2008 4:12 am

yes.

every third integer is a multiple of 3:
0 1 2 3 4 5 6 7 8 9 ... etc

so if you have the product of three consecutive integers, then one of them has to be a multiple of 3 (colored in red).

furthermore, as another poster has pointed out, this is the case not just for 3, but for an arbitrary # of consecutive integers.
cutlass
 
 

by cutlass Mon May 05, 2008 4:58 pm

Ok. That confirms my understanding.
StaceyKoprince
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by StaceyKoprince Thu May 08, 2008 1:28 am

Excellent! Glad it helped!
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