## BDMO REGIONAL 2015

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Joined: Mon Jan 23, 2017 10:32 am

### BDMO REGIONAL 2015

Help me to solve this......
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aritra barua
Posts: 57
Joined: Sun Dec 11, 2016 2:01 pm

### Re: BDMO REGIONAL 2015

Note that the distinct numbers are repeated according to their intrinsic values.Find their summation noticing that the summation of a distinct pair is equal to the square of that distinct pair.Find the remainder which shows that the division upon a number by 3 leaves the same remainder as it does upon the division of the summation of that number by 3.It is easy to prove this fact using modular arithmetic.