Question

find the sum of 100 odd number starting with 1

Answer 1

So we can do the following: Sumof odd consecutive integers from1 to 100 = (Sum of all consecutive integers from 1 to100) - (Sum of even consecutiveintegers from 1 to 100). Sum of odds = (100 x 101/2) - [2 x (50 x 51/2)] = 5050 - 2550 = 2500. Now, the set {3,5,7,9...101} requires us to consider 3 to 101 not 1 -100.

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