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The sum of three consecutive integers is -87. What are the integers?
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-30, -29, -28.
Notice that the middle number of these three is exactly one third of their sum.
It is not an occasional coincidence. It is the RULE.
Indeed, if the tree numbers are (x-1), x, and (x+1) with the middle "x", then their sum is Sum = (x-1) + x + (x+1) = 3x
and x =
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