Ratio, Proportion


  1. The ratio of monthly incomes of A, B is 6 : 5 and their monthly expenditures are in the ratio 4 : 3. If each of them saves ₹ 400 per month, find the sum of their monthly incomes.









  1. View Hint View Answer Discuss in Forum

    Income of A and B = ₹ 6x and 5x
    Expenses of A and B = ₹ 4y and 3y
    ∴  6x – 4y = 400      ...(i)
    5x – 3y = 400      ...(ii)
    By equation (i)× 3 – (ii) × 4
    ⇒  18x – 12y –20x + 12y
    = 1200 – 1600
    ⇒  2x = 400 ⇒ x = 200
    ∴  Total income
    = 6x + 5x = 11x = ₹ 2200

    Correct Option: C

    Income of A and B = ₹ 6x and 5x
    Expenses of A and B = ₹ 4y and 3y
    ∴  6x – 4y = 400      ...(i)
    5x – 3y = 400      ...(ii)
    By equation (i)× 3 – (ii) × 4
    ⇒  18x – 12y –20x + 12y
    = 1200 – 1600
    ⇒  2x = 400 ⇒ x = 200
    ∴  Total income
    = 6x + 5x = 11x = ₹ 2200


  1. Annual incomes of Amit and Veeri are in the ratio 3:2, while the ratio of their expenditure is 5 : 3. If at the end of the year each saves ₹ 1,000, the annual income of Amit is









  1. View Hint View Answer Discuss in Forum

    Amit’s income = ₹ 3x and his expenditure = ₹ 5y
    Veeri’s income = ₹ 2x and his expenditure = ₹ 3y
    ∴  3x – 5y = 2x – 3y
    ⇒  x = 2y
    ∴  3x – 5y = 1000
    ⇒  6y – 5y = 1000 ⇒ y = 1000
    ∴  x = 2000
    ∴  Amit’s income
    = 3x = 3 × 2000 = ₹ 6000

    Correct Option: D

    Amit’s income = ₹ 3x and his expenditure = ₹ 5y
    Veeri’s income = ₹ 2x and his expenditure = ₹ 3y
    ∴  3x – 5y = 2x – 3y
    ⇒  x = 2y
    ∴  3x – 5y = 1000
    ⇒  6y – 5y = 1000 ⇒ y = 1000
    ∴  x = 2000
    ∴  Amit’s income
    = 3x = 3 × 2000 = ₹ 6000



  1. If the annual income of A, B and C are in the ratio 1 : 3 : 7 and the total annual income of A and C is ₹
    8,00,000, then the monthly salary of B (in ₹ ) is









  1. View Hint View Answer Discuss in Forum

    Let Annual Income of A, B and C be x, 3x and 7x
    x + 7x = 800000
    ⇒  8x = 800000
    ⇒  x = 100000
    ∴  B’s monthly income

    =
    100000 × 3
    12

    = ₹ 25000

    Correct Option: B

    Let Annual Income of A, B and C be x, 3x and 7x
    x + 7x = 800000
    ⇒  8x = 800000
    ⇒  x = 100000
    ∴  B’s monthly income

    =
    100000 × 3
    12

    = ₹ 25000


  1. Ratio between the monthly incomes of A and B is 9 : 8 and the ratio between their expenditures is 8 : 7. If they save ₹ 500 each, find A’s monthly income.









  1. View Hint View Answer Discuss in Forum

    If the ratio of the income of A and B be a : b and that of their expenses be c : d and each saves ₹ x, then,

    A’s income =
    ax(d − c)
    ad − bc

    =
    9 × 500(7 − 8)
    9 × 7 − 8 × 8

    = 9 × 500 = ₹ 4500

    Correct Option: C

    If the ratio of the income of A and B be a : b and that of their expenses be c : d and each saves ₹ x, then,

    A’s income =
    ax(d − c)
    ad − bc

    =
    9 × 500(7 − 8)
    9 × 7 − 8 × 8

    = 9 × 500 = ₹ 4500



  1. Incomes of A and B are in the ratio 4 : 3 and their annual expenses in the ratio 3 : 2. If each saves ₹ 60,000 at the end of the year, the annual income of A is









  1. View Hint View Answer Discuss in Forum

    Let the annual income of A and B be ₹ 4x and ₹ 3x and their income be Rs. 3y and Rs. 2y. respectively.
    ∴  4x – 3y = 60000      ...(i)
    and 3x – 2y = 60000      ...(ii)
    Clearly, 4x – 3y = 3x – 2y
    ⇒  x = y
    From equation (i),
    x = 60000
    ∴  A’s annual income
    = 4x = 4 × 60000
    = ₹ 240000

    Correct Option: C

    Let the annual income of A and B be ₹ 4x and ₹ 3x and their income be Rs. 3y and Rs. 2y. respectively.
    ∴  4x – 3y = 60000      ...(i)
    and 3x – 2y = 60000      ...(ii)
    Clearly, 4x – 3y = 3x – 2y
    ⇒  x = y
    From equation (i),
    x = 60000
    ∴  A’s annual income
    = 4x = 4 × 60000
    = ₹ 240000