SOLUTION: The 5th term of a geometric progression is 4375 and it 2nd term is 35.find the 3rd term.

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Question 947272: The 5th term of a geometric progression is 4375 and it 2nd term is 35.find the 3rd term.
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Use what you understand for geometric progressions.

a, a*r, a*r^2, a*r^3, a*r^4, a*r^5.

a, 35, a*r^2, a*r^3, 4375.

Those two sequences must be equal. What more can you determine?

35%2Ar=a%2Ar%5E2;
35%2Ar%5E3=4375.
You should be able to find r.


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common ratio is 5.
r=5.
a=7.
Term with index 3 is 35*5=175.