Sumali sa IDNStudy.com at makuha ang mga sagot ng eksperto. Tuklasin ang libu-libong mga sagot na na-verify ng mga eksperto at hanapin ang mga solusyong kailangan mo, anuman ang paksa.

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.