Q7 of 102 Page 410

Find the sum of the series 2 + 5 + 8 + 11 + …. + 191.

To Find: The sum of the given series.


The nth term of an AP series is given by


tn = a + (n - 1)d


⇒191 = 2 + (n - 1)3


⇒3(n - 1) = 189


⇒n - 1 = 63


⇒n = 64


Therefore,


= 32 × 193 = 6176


The sum of the series is 6176.


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