SOLUTION: a4=24 a7=64/9 Find An Find Sn

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Question 1029525: a4=24 a7=64/9
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Found 2 solutions by Fombitz, MathTherapy:
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
A%5B4%5D=A%5B1%5D%2B%284-1%29d=A%5B0%5D%2B3d=24
A%5B7%5D=A%5B1%5D%2B%287-1%29d=A%5B0%5D%2B6d=64%2F9
Subtracting,
A%5B1%5D%2B6d-A%7B1%5D-3d=64%2F9-24
3d=-152%2F9
d=-152%2F27
So then,
A%5B1%5D%2B3%28-152%2F27%29=24
A%5B1%5D-152%2F9=216%2F9
A%5B1%5D=368%2F9
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A%5Bn%5D=368%2F9%2B%28n-1%29%28-152%2F27%29
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S%5Bn%5D=%28n%2F2%29%28A%5B1%5D%2BA%5Bn%5D%29
S%5Bn%5D=+%28n%2F2%29%28368%2F9%2B368%2F9%2B%28n-1%29%28-152%2F27%29%29+
S%5Bn%5D=%284%2F27%29n%28295-19n%29

Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!

a4=24 a7=64/9
Find An
Find Sn
Don't you think you need to state whether this is an AP or GP?

If you should decide to do so, I MIGHT give you the answer, or even work it out for you.