The firstand last terms of an A.P. are 1 and 11. If the sum of its ter – InterviewSolution

1.	The firstand last terms of an A.P. are 1 and 11. If the sum of its terms is 36, thenthe number of terms will be(a) 5 (b) 6 (c) 7 (d) 8
Answer» Correct Answer - 6 `n/2 (a+l) =36 Rightarrow n/2 xx(1+11) =36 Rightarrow n=6`

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