SOLUTION: The second term of the geometric sequence is 250, and the fifth term is 16. Find the seventh term.

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Question 1166515: The second term of the geometric sequence is 250, and the fifth term is 16. Find the seventh term.
Answer by ikleyn(52788) About Me  (Show Source):
You can put this solution on YOUR website!
.

    a%5B5%5D = r%5E4%2Aa%5B1%5D

    a%5B2%5D = r%5E1%2Aa%5B1%5D


    a%5B5%5D%2Fa%5B2%5D = r%5E3 = 250%2F16 = 15.625


    r = root%283%2C15.625%29 = 2.5


    a%5B7%5D = r%5E2%2Aa%5B5%5D = 2.5%5E2%2A16 = 40.    ANSWER

Solved.

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On geometric progressions, see the lessons
    - Geometric progressions
    - The proofs of the formulas for geometric progressions
    - Problems on geometric progressions
    - Solved problems on geometric progressions
    - Word problems on geometric progressions
    - One characteristic property of geometric progressions
    - Fresh, sweet and crispy problem on arithmetic and geometric progressions


Also, you have this free of charge online textbook in ALGEBRA-II in this site
    - ALGEBRA-II - YOUR ONLINE TEXTBOOK.

The referred lessons are the part of this online textbook under the topic
"Geometric progressions".