SOLUTION: The 6 term in geometric progression is 96 and the 9 term is 768. Find the sum of the first 8 terms to 11 terms

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Question 727850: The 6 term in geometric progression is 96 and the 9 term is 768.
Find the sum of the first 8 terms to 11 terms
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Your question is uncertain. You may be asking for the sum of terms indexed 8 through 11.

The index 6 and 9 terms require a factor of 8. The common ratio used for the geometric sequence is 2. If you focus on term of index 6 being 96, divide by 8, you get the term at index 3 which is 12. To get to index 1 term, divide 12 by 2, twice. The first term of the sequence is 3. You do not really need the first term if you want the sum of terms indexed 8 through 11.

Term indexed 8 would be the n=9 term, 768 divided by 2.
Term number 8 is 768%2F2
Term number 9 is 768
Term number 10 is 768%2A2
Term number 11 is 768%2A2%2A2
Just find the sum of these four terms.