Q1 of 110 Page 64

Find the sum of the following series.

1 + 2 + 3 + …. + 45

Given that series S = 1 + 2 + 3 + 4 + 5… + 45, it has n = 45 terms and to find the sum S.


Formula for sum of first n numbers is


S =




45x23


= 1035


The sum S = 1 + 2 + 3 + … + 45 = 1035


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