SOLUTION: Find the sum of the first 90 odd numbers

Algebra.Com
Question 392612: Find the sum of the first 90 odd numbers
Answer by richard1234(7193)   (Show Source): You can put this solution on YOUR website!
There's a well known formula that the sum of the first n odd numbers is n^2 (can you prove it works for all positive n?). Using this, the sum of the first 90 odd numbers is 90^2, or 8100.
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