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Consider an A.P. a(1), a(2), "……"a(n), "...

Consider an `A.P. a_(1), a_(2), "……"a_(n), "……."` and the G.P. `b_(1),b_(2)"…..", b_(n),"….."` such that `a_(1) = b_(1)= 1, a_(9) = b_(9)` and `sum_(r=1)^(9) a_(r) = 369`, then

A

`b_(6) = 27`

B

`b_(7) = 27`

C

`b_(8) = 81`

D

`b_(9) = 81`

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A
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