math B30
posted by alix .
If the seventh term of a geometric series is 192, and the first term is 3, find the sum of the first 8 terms of the series

math B30 
Reiny
ar^6 = 192 , a=3
r^6 = 192/3 = 64
r = 2
sum(8) =a(r^8  1)/(r1)
= 3(2561)/(21) = 765 
math B30 
alix
i don't understand how you get r?

math B30 
alix
nvm i got i thank you so much

math B30 
Common difference
Mathe matics
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