A person is to cout 4500 currency notes....

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

24 minutes

34 minutes

125 minutes

135 minutes

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A person is to count 4500 currency notes. Let an denote the number of notes he counts in the nth minute. If a_1=""a_2="". . . . . .""=""a_(10)=""150 and a_(10),""a_(11),"". . . . . . are in A.P. with common difference 2, then the time taken by him to count all notes is (1) 34 minutes (2) 125 minutes (3) 135 minutes (4) 24 minutes

A person is to count 4500 currency notes. Let a_n, denote the number of notes he counts in the nth minute if a_1=a_2=a_3=..........=a_10=150 and a_10,a_11,.........are in an AP with common difference -2, then the time taken by him to count all notes is :- (1) 24 minutes 10 11 (2) 34 minutes (3) 125 minutes (4) 135 minutes

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