SOLUTION: Given the arithmetic progression -1/6,1/12,1/3...find the 10th term and the sum of the 12 terms

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Question 778639: Given the arithmetic progression -1/6,1/12,1/3...find the 10th term and the sum of the 12 terms
Answer by psbhowmick(878) About Me  (Show Source):
You can put this solution on YOUR website!
The n-th term for an A.P. series with first term a and common difference d is given by t%5Bn%5D=a%2B%28n-1%29d.

Here, a=-1%2F6, d+=+1%2F12-%28-1%2F6%29=1%2F12%2B1%2F6=3%2F12=1%2F4.
t%5B10%5D=-1%2F6%2B%2810-1%29%281%2F4%29
t%5B10%5D=-1%2F6%2B9%2F4=%28-2%2B27%29%2F12=25%2F12