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by preetha_85 » Sun Jul 27, 2008 6:02 am
Hi
All you need to do is add the first row i.e 1+2+...+7 =28
The 2nd can be represented as : -2( 1+2+...+7) =-56
The 3rd can be represented as : 3( 1+2+...+7) =84
nd so on till the 7th row.

The answer therefore is 28-56+84-112+140-168+196 = 112.

Is the OA the same ?
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by sudhir3127 » Sun Jul 27, 2008 6:34 am
Please use the search function before posting a new question..

Answer is 112. if u see the question , u will notice that the middle term of each row is the average of the that particular row.

So u just need to total the middle numbers of each row and multiply by 7.

hence 16*7 = 112.

hope thats clear.
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by malolakrupa » Mon Jul 28, 2008 10:10 am
Alternatively it evaluates to

28(1-2+3-4+5-6+7) = 28*4 = 112
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