Question 634525: 1+2+3+4+5+6+7+8+9+10+..........+97+98+99
Answer by Alan3354(69443)   (Show Source):
You can put this solution on YOUR website! 1+2+3+4+5+6+7+8+9+10+..........+97+98+99
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That's the sum of 99 numbers. Put a zero in front:
0+1+2+3+4+5+6+7+8+9+10+..........+97+98+99
Now there are 100 numbers.
Make them 50 pairs: 0+99, 1+98, 2+97, etc
--> 50 pairs, each pair is 99
50*99 = 4950
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Or use Excel
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