Putting It Together

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Holmez
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Suppose you have a list of numbers from zero to one hundred. How quickly can you add them all up without using a calculator?

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HINT: There is a swift way to add these numbers. Think about how the numbers at the opposite ends of the list relate to each other.
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SOLUTION: The list contains fifty pairs of numbers that add to 100 (100+0, 99+1, 98+2, 97+3, etc.) with the number 50 as an unpaired leftover: 50 X 100 + 50 = 5,050
Source:Critical Thinking Puzzles – by Michael A. DiSpezio