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Export to Excel select * from life where title = 'Adding' order by date desc,ordinal ( Row)
Sun, Jul 15 2007 1100 Adding Gauss was six years old when,
one day the teacher was fed up
with the paper airplanes, so she told the kids to
add up all the numbers from one to a hundred
while she is going out for coffee.

5050, he said, before she left for the door.

How did you know? she panicked.

Its simple really:
Add the first to the last, you get 101.
Add 99 to 2, still 101.
Add 98 to 3...
Add all the way to 50+51.

Counting 50 times 101 in all.

1+ 2 + 3 +...+ n = n*(n+1)/2

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