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Algebra Difficulty 4.1 AIME Find the answer South Africa
What is the value of (2+4+6+...+198+200)−(1+3+5+...+197+199)?
A number or a short expression. Fractions can be typed as 3/2, and spacing doesn't matter.
Solution
Rearranging, the value is (2−1)+(4−3)+(6−5)+⋯+(200−199) which has 100 brackets and therefore totals 100×1=100.
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