In an A.P.,the first term is 22, `n t h`term is `-11`and the sumto fir – InterviewSolution

InterviewSolution

1.	In an A.P.,the first term is 22, `n t h`term is `-11`and the sumto first `n`terms is66. Find `n`and `d`, thecommon difference.
Answer» Correct Answer - n = 12, d = -3 `S_(n) = (n)/(2)(a+l) rArr (n)/(2)[22 +(-11)] = 66 rArr n = 12.` `T_(12) =-11 rArr a + 11d = -11 rArr 22 + 11d = -11 rArr d = -3.`

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