Home
Class 12
MATHS
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

A

34 minutes

B

24 minutes

C

125 minutes

D

35 minutes

Text Solution

Verified by Experts

The correct Answer is:
A
Promotional Banner

Topper's Solved these Questions

  • SEQUENCE AND SERIES

    VK JAISWAL|Exercise EXERCISE (ONE OR MORE THAN ONE ANSWER IS/ARE CORRECT)|19 Videos
  • SEQUENCE AND SERIES

    VK JAISWAL|Exercise EXERCISE (COMPREHENSION TYPE PROBLEMS)|17 Videos
  • QUADRATIC EQUATIONS

    VK JAISWAL|Exercise EXERCISE (SUBJECTIVE TYPE PROBLEMS)|45 Videos
  • SOLUTION OF TRIANGLES

    VK JAISWAL|Exercise Exercise-5 : Subjective Type Problems|13 Videos

Similar Questions

Explore conceptually related problems

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

If a_(n) denotes the nth term of the AP 2, 7, 12, 17,…., find the value of (a_(30)-a_(20))

nth term of an AP is a_(n). If a_(1)+a_(2)+a_(3)=102 and a_(1)=15, then find a_(10)

If a_(1),a_(2),a_(3),a_(4) and a_(5) are in AP with common difference ne 0, find the value of sum_(i=1)^(5)a_(i) " when " a_(3)=2 .

If in an A.P. a_(7)=9 and if a_(1)a_(2)a_(7) is least, then common difference is _____

Let a_(n) be the nth term of an AP, if sum_(r=1)^(100)a_(2r)=alpha " and "sum_(r=1)^(100)a_(2r-1)=beta , then the common difference of the AP is

If a_(n) denotes the nth term of the AP 3, 18, 13, 18,… then what is the value of (a_(30)-a_(20))?

VK JAISWAL-SEQUENCE AND SERIES -EXERCISE (SUBJECTIVE TYPE PROBLEMS)
  1. A person is to cout 4500 currency notes. Let a(n) denotes the number o...

    Text Solution

    |

  2. Let a ,b ,c ,d be four distinct real numbers in A.P. Then half of the ...

    Text Solution

    |

  3. The sum of all digits of n for which sum (r =1) ^(n ) r 2 ^(r ) = 2+2^...

    Text Solution

    |

  4. If lim ( x to oo) (r +2)/(2 ^(r+1) r (r+1))=1/k, then k =

    Text Solution

    |

  5. The value of sum (r =1) ^(oo) (8r)/(4r ^(4) +1) is equal to :

    Text Solution

    |

  6. Three distinct non-zero real numbers form an A.P. and the squares of t...

    Text Solution

    |

  7. which term of an AP is zero -48,-46,-44.......?

    Text Solution

    |

  8. In an increasing sequence of four positive integers, the first 3 terms...

    Text Solution

    |

  9. The limit of (1)/(n ^(4)) sum (k =1) ^(n) k (k +2) (k +4) as n to oo i...

    Text Solution

    |

  10. Which is the last digit of 1+2+3+……+ n if the last digit of 1 ^(3) + ...

    Text Solution

    |

  11. There distinct positive numbers, a,b,c are in G.P. while log (c) a, lo...

    Text Solution

    |

  12. The numbers 1/3, 1/3 log (x) y, 1/3 log (y) z, 1/7 log (x) x are in H...

    Text Solution

    |

  13. If sum ( k =1) ^(oo) (k^(2))/(3 ^(k))=p/q, where p and q are relativel...

    Text Solution

    |

  14. The sum of the terms of an infinitely decreassing Geometric Progressio...

    Text Solution

    |

  15. A cricketer has to score 4500 runs. Let a (n) denotes the number of ru...

    Text Solution

    |

  16. If x=10 sum(r=3) ^(100) (1)/((r ^(2) -4)), then [x]= (where [.] deno...

    Text Solution

    |

  17. Let f (n)=(4n + sqrt(4n ^(2) +1))/( sqrt(2n +1 )+sqrt(2n-1)),n in N th...

    Text Solution

    |

  18. Find the sum of series 1+1/2+1/3+1/4+1/6+1/8+1/9+1/12+…… oo, where the...

    Text Solution

    |

  19. Let a (1), a(2), a(3),…….., a(n) be real numbers in arithmatic progres...

    Text Solution

    |

  20. Let the roots of the equation 24 x ^(3) -14x ^(2) + kx +3=0 form a geo...

    Text Solution

    |

  21. How many ordered pair (s) satisfy log (x ^(2) + (1)/(3) y ^(3) + (1)/(...

    Text Solution

    |