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If x,y,z be three numbers in G.P. such t...

If `x,y,z` be three numbers in `G.P.` such that `4` is the `A.M.` between `x` and `y` and `9` is the `H.M.` between `y` and `z` , then `y` is

A

`4`

B

`6`

C

`8`

D

`12`

Text Solution

Verified by Experts

The correct Answer is:
B

`(b)` Let `x=(k)/(r )`, `y=k`, `z=kr`
`implies((k)/(r )+k)/(2)=4` ……..`(i)`
and `(2k*kr)/(k+kr)=9` ………`(ii)`
Solving we get `k=6`
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