SOLUTION: in the sequence, 3ˏ7/3ˏ5/3ˏ… what term is −17

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Question 933943: in the sequence, 3ˏ7/3ˏ5/3ˏ… what term is −17
Found 2 solutions by stanbon, Edwin McCravy:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
in the sequence, 3ˏ7/3ˏ5/3ˏ… what term is −17
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Arithmetic Sequence with a = 3 and d = -2/3
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Solve:: a + (n-1)d = -17
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3 + (n-1)(-2/3) = -17
(n-1)(-2/3) = -20
(n-1) = -20/(-2/3)
n-1 = 30
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Ans: n = 31st term
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Cheers,
Stan H.
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Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!
The 3 is really 9%2F3

9%2F3, 7%2F3, 5%2F3, ...

This is an arithmetic sequence with first term a%5B1%5D=3 and common
difference -2%2F3

a%5Bn%5D=a%5B1%5D%2B%28n-1%29d

-17=3%2B%28n-1%29%28-2%2F3%29

Solve that and get n=31, so -17 is the 31st term.

Edwin