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Find the sum of the following AP's (i) 5,7,9,11,...to 18terms |
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Answer» a=5 ,d=2 ,n=18 18TH term = a+17d = 5+17(2) i.e. 18th term or LAST term is 39 now, sum of TERMS = n/2(first term + last term) i.e. 18/2(5+39) 9(44)= 396 answer is 396 |
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