IDNStudy.com, ang komunidad ng pagbabahagi ng kaalaman. Ang aming mga eksperto ay nagbibigay ng mabilis at eksaktong sagot upang tulungan kang maunawaan at malutas ang anumang problema.

Four years ago, Antonio is three times the age of his daughter Diana. In 10 years, he will be twice her age. How old are they now?

Sagot :

This is what the statement means in mathematical form.

Let:       y = age of Diana
             x = age of Antonio

x - 4 = 3 (y-4)
x + 10 = 2 (y + 10)

        x -4    = 3y - 12
    -   x+10 = 2y + 20
      0 -14 =   y  - 32
           
           -14 = y - 32
   -14 + 32 = y
            18 = y

x + 10 = 2y + 20
x        = 2y + 20 -10
x        = 2y + 10
x         = 2(18) + 10
x         = 36 + 10
x         = 46

Antonio's present age is 46 years old.
Diana's present age is 18 years old.

Check:
           4 years ago, Antonio's age is 3 times the age of Diana.
    46 - 4 = 18 - 4
     42      = 14

42 is 3 times 14, Correct.
  
          In 10 years, Antonio's age will be twice the age of Diana.
46 + 10 = 18 + 10
56 = 28
56 is twice of 28, Correct.