The ninth and tenth terms of an arithmetic sequence are and ​, respectively. What is the second term?

If you understand the answer to solving the problem given the 16^th and 17^th terms, work this problem in a similar fashion.

1/4 is equivalent to 3/12 

1/3 is equivalent to 4/12 

So if we conclude that this arithmetic sequence is the addition of 1/12 to each term, then: 

–5/12   –4/12   –3/12   –2/12   –1/12   0/12   1/12   2/12   3/12   4/12 

  1st       2nd      3rd       4th        5th     6th     7th     8th     9th    10th 

second term –4/12  =  –1/3 

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