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Jalishapink
what is the sum of term of the series(-1)+(-2)+(-3) + + (-10) what is the sum of the first five terms of the series 35+30+25 + what is the sum of the last four terms of the series 7+9+11+ + 21 what is the sum of the first terms of the series 7+12+17+
(-1)+(-2)+(-3) + + (-10) start by identifying the common difference of this series ?
use AP for the purpose... formula that would be used here is (n/2)(2a+(n-1)d) where n = no. of terms a = first term of the AP and d = common difference