Find the sums given below:

34 + 32 + 30 +….+10


The sum of the series given by

Sn = [2a + (n-1) d]


Where n is the last term in the series


d is the common difference


a is the first term.


an = 10, a = 34


d = n2 – n1 = 32 - 34 = 2


an = a + (n-1)d


10 = 34 + (n-1)(-2)


-24 = -2(n-1)


12 = n-1


n = 13


The sum of the series is Sn = [2a + (n-1) d]


= [ 2×34 + (13-1)(-2)]


= [ 44 ] 286


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