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The 4th and 7th terms of a G.P. are 1/(2...

The 4th and 7th terms of a G.P. are `1/(27)a n d1/(729)` respectively. Find the sum of `n` terms of the G.P.

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Given,4th term =`ar^3=1/27`
​ also,7th term =`ar^6=1/729`
​ so
`(ar^6)/(ar^3)=(1/729)​/(1/27)​`
`⇒r=1/3​`
...
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