SOLUTION: What is the sum of the 1st 500 counting digits? That is what is the sum of 1+2+3+4+...+499+500? How about the sum of only the odd digits, 1+3+5+...+497+499?

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Question 11118: What is the sum of the 1st 500 counting digits? That is what is the sum of 1+2+3+4+...+499+500? How about the sum of only the odd digits, 1+3+5+...+497+499?
Answer by askmemath(368) About Me  (Show Source):
You can put this solution on YOUR website!
Sum of the first n counting digits = n(n+1)/2
So for first 500 = 500x501/2 = 250 x 501 = 125250
Sum of first n odd numbers = n^2
Check:
Sum of first 3 odd numbers = 1+3+5 = 9
n^2 = 3^2 = 9 Yay!!