Post a New Question

Kathie

posted by .

In four years' time, a father will be three times as old as his son. Six years ago, he was seven times as old as his son. How old are they now? Explain your workings. Thanks

  • Kathie -

    son's present age: x
    father's present age : y

    4 yrs from now:
    son : x+4
    father : y+4
    y+4 = 3(x+4)
    y = 3x + 8

    6 yrs ago:
    son : x-6
    father: y-6
    y - 6 = 7(x-6)
    y = 7x -36

    so 7x -36 =3x+8
    4x = 44
    x = 11
    y = 3(11)+8 = 41

    The son is now 11 and the father is now 41

    check:
    4 yrs from now: son-- 15, father 45
    3 times as old? yes

    6 yrs ago: son -- 5, father 35
    7 times as old? yes

    all is good

  • Kathie -

    Thank you very much Reiny!

Answer This Question

First Name
School Subject
Your Answer

Related Questions

More Related Questions

Post a New Question