SOLUTION: which term of the sequence 5,7/2,2....is -19

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Question 946811: which term of the sequence 5,7/2,2....is -19
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
The common difference is 7%2F2-5=7%2F2-10%2F2=-3%2F2.
The first term is 5.
So,
a%5Bn%5D=5-%283%2F2%29%28n-1%29
When a%5Bn%5D=-19, then,
5-%283%2F2%29%28n-1%29=-19
-%283%2F2%29%28n-1%29=-24
n-1=16
n=17
The 17th term.