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as he walks towards the Du40. The sum of first 8 term of an AP is 100 and sum of first 19 terms is 551. Find APOR |
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Answer» Let a be first term and d be common differenceA/q(8/2)[2a+(8-1)d] = 100⇒2a + 7d =25_____(1)and (19/2)[2a + (19-1)d] = 551⇒2a + 18d = 58____(2)subtracting equation (1) and (2)11d = 33⇒d = 3so a = (25 - 21)/2 = 2so, 2,5,8.11,14....... |
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