SOLUTION: Evaluate the sum: 1-2+3-4+5-6+7-8+9-10+�-998+999-1000

SOLUTION: Evaluate the sum: 1-2+3-4+5-6+7-8+9-10+�-998+999-1000

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Question 252456: Evaluate the sum: 1-2+3-4+5-6+7-8+9-10+�-998+999-1000
Answer by drk(1908) (Show Source): You can put this solution on YOUR website!
Evaluate the sum: 1-2+3-4+5-6+7-8+9-10+�-998+999-1000
Notice that each pair of number adds to -1.
There are 500 such pairs, so,
500*(-1) = -500.
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