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805+ (Hard)|   Sequences|               
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Please correct me if I'm wrong Bunuel KarishmaB

I did it by the formula
7th term of 13 notes, increasing in a fixed ratio, will be the average

average of a GP = (AB)^1/2
hence, (880*440)^1/2
= 440*(2)^1/2
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ga821
Please correct me if I'm wrong Bunuel KarishmaB

I did it by the formula
7th term of 13 notes, increasing in a fixed ratio, will be the average

average of a GP = (AB)^1/2
hence, (880*440)^1/2
= 440*(2)^1/2

Yes, the solution is perfect. If you understand GP and GM well, solving the question would take 10 secs. It is square root of 440 * 440 *2 which means 440*sqrt2.
It illustrates the point that we don't NEED to know GP etc. for GMAT but knowing them nevertheless helps.
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