SOLUTION: Find the common ratio of the geometric sequence with a first term -7 and a sixth term -1701.

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Question 1141039: Find the common ratio of the geometric sequence with a first term -7 and a sixth term -1701.
Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!

Let the common ratio be r, then we write out the expressions for the first
6 terms by starting with -7 and finding each successive term by multiplying
the preceding term by r.  Then when we get to the sixth one we set it equal
to -1701.

-7, -7r, -7r2, -7r3, -7r4, -7r5 = -1701 

So we solve: 

-7r5 = -1701 

Divide both sides by -7

r5 = 243

Take 5th roots of both sides:

root%285%2Cr%5E5%29=root%285%2C243%29

r = 3    <-- common ratio.

FYI the sequence is -7, -21, -63, -189, -567, -1701

Edwin