if you look at the table you will notice the 1st row = 28. Each subsequent row is a mult of 7
row 1)28 2)-56 3)84.........7)196 ad them up & you get 112
hope it helps
ps
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santa_dem
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The simpliest approach, in my opinion:
Lets say the sum of the first row is x.
The sum of the second row will be -2x, and then keep going:
x
-2x
3x
-4x
5x
-6x
7x.
So the sum of the entire table is 4x, were x is 28. So the entire table sums up to 112.
Lets say the sum of the first row is x.
The sum of the second row will be -2x, and then keep going:
x
-2x
3x
-4x
5x
-6x
7x.
So the sum of the entire table is 4x, were x is 28. So the entire table sums up to 112.
