The multiplication of the age of Rajiv, before 5 years and after 9 years, is 15 :

The multiplication of the age of Rajiv, before 5 years and after 9 years, is 15. What is the present age of Rajiv ?
(a) 6
(b) 7
(c) 5
(d) 8

Anurag Mishra Professor Asked on 10th February 2016 in Maths.
Add Comment
  • 1 Answer(s)

    Answer: (a) 6

    Solution:-
    Let the present age of Rajiv be X years

    The multiplication of the age of Rajiv, before 5 years and after 9 years.
    Then, (X – 5) (X + 9) = 15
    X2 + 9 X – 5X – 45 = 15
    X2 + 4 X – 45 – 15 =0
    X2 + 4 X – 60 = 0
    X2  + 10 X – 6 X – 60 = 0
    X (X + 10 ) – 6 (X + 10) = 0
    (X – 6) (X + 10) = 0
    X – 6 = 0
    X = 6

    Then, the present age of Rajiv is 6 years.

    Hence, the correct answer is option (a) 6 years.

    Anurag Mishra Professor Answered on 10th February 2016.
    Add Comment
  • Your Answer

    By posting your answer, you agree to the privacy policy and terms of service.