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Find the sum of 1+5+9........325? |
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Answer» -STEP EXPLANATION:here a = 1, d = 4, an =325a + (n - 1)d = 3251 + 4n - 4 = 3254n = 328n = 328 / 4 = 82therefore nth term is 325 and we have to FIND the sum of the series upto 82nd term.Sn = (n / 2)( a + an ) = (82 / 2)(1 + 325) = 41 x 326 = 13366 |
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