Number System


  1. Divide 50 into two parts so that the sum of their reciprocals is 1/12 ?









  1. View Hint View Answer Discuss in Forum

    Let the number be N and (50 - N)
    Then, 1/N + 1/(50-N) = 1/12

    Correct Option: A

    Let the number be N and (50 - N)
    Then, 1/N + 1/(50-N) = 1/12
    ⇒ (50 - N + N) / {N(50 - N)} = 1/12
    ⇒ N2 - 50N + 600 = 0
    ⇒ N = 30 or 20
    ∴ the number are 20, 30


  1. The ratio between two numbers is 2 : 3. If the consequent is 24, the antecedent is ?









  1. View Hint View Answer Discuss in Forum

    Let the antecedent be N.
    Then, N/24 = 2/3

    Correct Option: B

    Let the antecedent be N.
    Then, N/24 = 2/3
    ⇒ N = (24 x 2) / 3
    = 16



  1. If a number is subtracted from the square of its one half, the result is 48. The square root of the number is ?









  1. View Hint View Answer Discuss in Forum

    Let the number be N.
    Then (N/2)2 - N = 48

    Correct Option: A

    Let the number be N.
    Then (N/2)2 - N = 48
    ⇒ N2/4 - N = 48
    ⇒N2 - 4N-192= 0
    ⇒ (N-16) (N+12) = 0
    ⇒ N = 16
    ∴ The square root of the number is 4.


  1. The sum of three consecutive number is given. What is the difference between first and third number ?









  1. View Hint View Answer Discuss in Forum

    Let the three consecutive numbers be x, x+1 and x+2 respectively
    ∴ Diff between first and third numbers = (x + 2) - x

    Correct Option: D

    Let the three consecutive numbers be x, x+1 and x+2 respectively
    ∴ Diff between first and third numbers = (x + 2) - x
    = 2



  1. A number gets reduced to its one-third, when 48 is subtracted from it. What is two-third of that number ?









  1. View Hint View Answer Discuss in Forum

    Let the number be N.
    Then, N - N/3 = 48

    Correct Option: D

    Let the number be N.
    Then, N - N/3 = 48
    2N/3 = 48.