Q: The sum of the first and last terms of a G.P. of fourteen real terms is 7. The fifth term is the mean proportional between the second and last terms. Find the third term.

All I have been able to come up with thus far are the equations:

t

and

t

Then I plugged in a for t

I tried to work through the two equations from here, solving one for a, then plugging that into the other equation to get r, then using r to get a, but I haven't been able to get an answer.

Any help is greatly appreciated.

All I have been able to come up with thus far are the equations:

t

_{1 }+ t_{14 }= 7and

t

_{2}/t_{5}= t_{5}/t_{14}Then I plugged in a for t

_{1}, ar for t_{2}, ar^{4}for t_{5,}and ar^{13}for t_{14}I tried to work through the two equations from here, solving one for a, then plugging that into the other equation to get r, then using r to get a, but I haven't been able to get an answer.

Any help is greatly appreciated.

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