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A person is to count 4500 currency notes...

A person is to count 4500 currency notes . Let `a_(n) ` denots the number of notes he counts in the `n^(th)` minute . If `a_(1) =a_(2) = cdots = a_(10) = 150 ` and `a_(10) , a_(11) , cdots , ` are in A.P with common difference -2 then the time taken by him to count all notes is

A

135 min

B

24 min

C

34 min

D

125 min

Text Solution

Verified by Experts

The correct Answer is:
C
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