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Let a1,a2,a3,... be in harmonic progress...

Let `a_1,a_2,a_3,...` be in harmonic progression with `a_1=5a n da_(20)=25.` The least positive integer `n` for which `a_n<0` `22` b. `23` c. `24` d. `25`

A

22

B

23

C

24

D

25

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The correct Answer is:
D
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