Ratio, Proportion


  1. The weight of a 13 m long iron rod is 23.4 kg. The weight of 6 m long of such rod wiil be ?









  1. View Hint View Answer Discuss in Forum

    Less length, less weigth
    From question, 13 : 6 : : 23.4 : W
    ⇒ 13 x W = 6 x 23.4

    Correct Option: C

    Less length, less weigth
    From question, 13 : 6 : : 23.4 : W
    ⇒ 13 x W = 6 x 23.4
    ∴ W = (6 x 23.4) /13 = 10.8 kg


  1. The third propotional to 0.8 and 0.2 is ?









  1. View Hint View Answer Discuss in Forum

    Let 0.8 : 0.2 : : 0.2 : N
    Then 0.8 x N = 0.2 x 0.2

    Correct Option: C

    Let 0.8 : 0.2 : : 0.2 : N
    Then 0.8 x N = 0.2 x 0.2
    ∴ N = ( 0.2 x 0.2) / 0.8 = 0.04 / 0.08 = 4/80 = 0.05



  1. The mean proportional between 0.32 and 0.02 is ?









  1. View Hint View Answer Discuss in Forum

    Mean proportional = √0.32 x 0.02

    Correct Option: D

    Mean proportional = √0.32 x 0.02
    = √0.0064 = 0.08


  1. The fourth proportional to 0.2, 0.12 and 0.3 is ?









  1. View Hint View Answer Discuss in Forum

    Let 0.2 : 0.12 : : 0.3 : N
    ∵ 0.2 x N = 0.12 x 0.3

    Correct Option: C

    Let 0.2 : 0.12 : : 0.3 : N
    ∵ 0.2 x N = 0.12 x 0.3
    ∴ N = (0.12 x 0.3) / 0.2 = 0.18



  1. What number should be subtracted from each of the number 54, 71, 75 and 99 so that the remainders may be proportional ?









  1. View Hint View Answer Discuss in Forum

    Let the required number be N,
    From question, (54 - N) / (71 - N) = (75 - N) / (99 - N)

    Correct Option: C

    Let the required number be N,
    From question, (54 - N) / (71 - N) = (75 - N) / (99 - N)
    ⇒ (54 - N) x (99 - N) = (75 - N) x (71 - N)
    ⇒ N2 - 153N + 5346 = N2 - 146N + 5325
    ⇒ 7N = 21
    ∴ N = 3