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    Find Out The Present Age of The Father and Son?

    Five years ago, the age of father was 7 times of his son. After five years, the age of the father will be 3 times of the age of the son. Find out the present age of the father and son.

    1. 36 years and 12 years
    2. 49 years and 7 years
    3. 20 years and 8 years
    4. 40 years and 10 years
    Asked by Anurag Mishra on 6th September 2015 in Maths.
    1 Answers
    Professor

    Answer:  (4) 40 years and 10 years
    Explanation:-

    Let the age of father be X years and the age of his son is Y years.
    Five years ago,
    (X – 5) = 7(Y – 5)
    X – 5 = 7Y – 35
    X – 7Y = -35 + 5
    X – 7Y = -30  ……………… (1)

    According to second condition,
    After five years,
    (X + 5) = 3(Y + 5)
    X + 5 = 3Y + 15
    X – 3Y = 15 – 5
    X – 3Y = 10 ………………….. (2)
    Equation (1) is subtract from equation (2),
    Then,
    X – 3Y –X + 7Y = 10 + 30
    4Y = 40
    Y = 40/4
    Y = 10 years
    Put the value of Y = 10 in equation (2),
    X – 3 x 10 = 10
    X = 10 + 30
    X = 40 years.

    Then, the present age of father is Y = 40 years and the present age of his son is X = 10 years

    Hence, the answer is (4) 40 years and 10 years.

    Answered by Anurag Mishra on 7th September 2015..