Ratio, Proportion


  1. The total number of students in school is 2140. If the number of girls in the school is 1200, then what is the ratio of the total number of boy to the total number of girls in the school ?









  1. View Hint View Answer Discuss in Forum

    Number of boy = ( 2140 - 1200 ) = 940

    Correct Option: B

    Number of boy = ( 2140 - 1200 ) = 940
    ∴ Boys : Girls = 940 : 1200 = 47 : 60


  1. The speed of three cars in the ratio of 2 : 3 : 4 Find the ratio between the time taken by these cars to cover the same distance ?









  1. View Hint View Answer Discuss in Forum

    Ratio of Speed = 2 : 3 : 4
    Ratio of time taken = (1/2) : (1/3) : (1/4)

    Correct Option: D

    Ratio of Speed = 2 : 3 : 4
    Ratio of time taken = (1/2) : (1/3) : (1/4) = 6 : 4 : 3



  1. If P : Q : = 8 : 15 and Q : R = 3 : 2, then find P : Q : R











  1. View Hint View Answer Discuss in Forum

    Given that, P : Q = 8 : 15, Q : R = 3 : 2
    P : Q : R = (8 x 3) : (15 x 3) : (15 x 2)

    Correct Option: C

    Given that, P : Q = 8 : 15, Q : R = 3 : 2
    P : Q : R = (8 x 3) : (15 x 3) : (15 x 2) = 24 : 45 : 30

    ∴ P : Q : R = 8 : 15 : 10
    Here, consequent of first ratio should be equal to the antecedent of second ratio.


  1. If P : Q = 8 : 15, Q : R = 5 : 8 and R : S = 4 : 5, then P : S is equal to











  1. View Hint View Answer Discuss in Forum

    Given, P/Q = 8/15, Q/R = 5/8, R/S = 4/5
    ∴ P/S = (P/Q) x (Q/R) x (R/S)

    Correct Option: A

    Given, P/Q = 8/15, Q/R = 5/8, R/S = 4/5
    ∴ P/S = (P/Q) x (Q/R) x (R/S)
    ⇒ P/S = (8/15) x (5/8) x (4/5) = 4/15
    ∴ P : S = 4 : 15



  1. If A : B = 2 : 3, B : C = 5 : 7 and C : D = 3 : 10, then what is A : D equal to ?









  1. View Hint View Answer Discuss in Forum

    Here, A : B = 2 : 3, B : C = 5 : 7 and C : D = 3 : 10
    ∴ A/D = (A/B) x (B/C) x (C/D)

    Correct Option: A

    Here, A : B = 2 : 3, B : C = 5 : 7 and C : D = 3 : 10
    ∴ A/D = (A/B) x (B/C) x (C/D)
    = (2/3) x (5/7) x (3/10)
    = 1/7
    ∴ A : D = 1 : 7