a boy is 12 years old. his father is four times old. In x years' time, the father will be three times as old as the son. calculate the value of x.

Question

the father is 4*12 (12 is his son old)

Answer 1

Let us say the age of the boy in X years is 12+X since his current age is 12. His father who is four times old will be currently 4*12 = 48 years old. In X years, his father's age will be 48+X. It is given that in X years, father will be three times as old as the son. 

 

So, 48+X = 3(12+X).

 

48+X = 3*12+3*X

 

48+X = 36+3X

 

Rearranging,

 

3X-X = 48-36

 

2X = 12

 

X = 12/2 = 6 years

 

Solution Check:

 

His father will be 48+6 = 54 years in 6 years from now. The boy will be 12+6 = 18 years old in 6 years from now. 

 

54 = 3*18 which shows that his father's age is three times the age of the boy in 6 years.

 

Hope this helps.

Saravanan

Answer 2

Right now, the son is 12 and the father is 48.....correct.

In x years from now their ages will be 12+x and 48+x. and the father is three times the sons age, so

48+x = 3(12+x)

48+x = 36 +3x

12     =        2x

6       =         x

 

Let's check. In 6 years their ages will be 18 and 54....so the father is 3 times the sons age.