- Add 1st row and 2nd row ... you wil get back 1st row but in negative
- Add the resulting row with 3rd row -- you'll get back second row but with +ve sign
- Add the resulting row with 4th row -- will get back 2nd row with -ve sign
- Add resulting row with 5th - you'll get 3rd row
- Add resulting with 6th - you'll get 3rd row in -ve
- Add resulting with 7th - you'll get 4th row with +ve
- Add 4th row together: 112
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California4jx
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vishubn
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Many approaches have been discussed ! i rememebr ! one approach which i did when i saw the same problem !!
When u look at each row !! its in the form 1, 2 3 4 5 6 7 muliples !!
soooo it has to be form of some multiple of a number
so first row is 28 before i go to the second row calculation i know it will come with the number which will be arounda the principle of multiplicity
28
-56
so on....
x,-2x,3x,-4x,5x,-6x,7x=4x so x =28
there answer is 112
vishu
When u look at each row !! its in the form 1, 2 3 4 5 6 7 muliples !!
soooo it has to be form of some multiple of a number
so first row is 28 before i go to the second row calculation i know it will come with the number which will be arounda the principle of multiplicity
28
-56
so on....
x,-2x,3x,-4x,5x,-6x,7x=4x so x =28
there answer is 112
vishu
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