What least number of terms of the sequence 17, `15 4/5 , 14 3/5 `shoul – InterviewSolution

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1.	What least number of terms of the sequence 17, `15 4/5 , 14 3/5 `should be taken so the sum is negative.
Answer» `S_n=n/2(2a+(n-1)d)` `=n/2((a+l)/2)` `s_n<0` `(a+l)/2<0` `2a+(n-1)d<0` `2aL-(n-1)d` `2aL-(n-1)d` `34L-(n-1)-6/5` `170/6<+(n-1)` `170/6+1L.` `29.33`n=30`

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