Sum of Integers

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Source: — Problem Solving |

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by manulath » Sun Sep 28, 2008 9:22 am
C: 57

three consec number are to be divisible by 3

n, n+1, n+2
sum = 3n + 3 = which is divisible by 3
only 57 satisfies the req

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by Mani_mba » Sun Sep 28, 2008 9:37 am
IMO C.

The average of three consec nos (Sum/3) should be the second integer.

Only the third option is divisible by 3.

It is a good question. :)

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by cramya » Sun Sep 28, 2008 12:09 pm
The approach suggested by Manulath is the approach that needs to be used for these problems

x,x+1,x+2

x+x+1+x+2 = 3x+3 = 3 (x+1)

This shows that the sum must be a multiple of 3 and the only one that fits this condition is 57