Aptitude - Problems on Ages - Discussion

As it is said that father's age is 3 times more than his son's.

So father's present age 3x and son's age x.
After 8 yrs their age will be,
3x+8 = 5/2(x + 8),
3x+8 = ((5x)/2) + (40/2),
2 * (3x+8) = 5x + 40,
6x + 16 = 5x + 40,
x = 24.

So son's age will be 24.
And father's age will be 3x = 72.

Further 8 more years ie; after 16 years,
Son's age will be x+16 ie; = 40,
and father's age will be 3x+16 ie; =88,

Therefore (x+16) ÷ (3+16) = 2.2.

Let the age of son be x then age of father will be 4x so we have ratio of father and son equals to 4x:x again after 8 years this becomes 5/2x:x as we all know that difference of age remains same then to make it same multiply above by 2 so that it becomes 5x:2x.

Therefore in 8 years 4x becomes 5x hence x is equal to 8 putting the value we get the age equal to 40 and 16 respectively and after 8 more years it will become 48 and 24 and hence father's age will be twice of the son.

I think 2.5(x+16) = (4x+16).

@Amrutha.


The correct answer is 11:5.

Fathers present age :72
Son's present age :24
So ratio:- 3:1

After 8 years:
father's age: 80
son's age: 32
so ratio:- 5:2

Further 8 years after:
Father's age : 88
Son's age: 40
So ratio : 11:5 is the correct answer.

Son- x father- 3x BUT, it is said MORE than 3 times so x +3x= 4x.

Now, 8 years ahead, son= x+8 and father= 5/2*(x+8).
---> (x+8)=5/2*(x+8),
---> 2(x+8)=5(x+8),
---> 2x + 16= 5x + 40,
---> x= 8 - sons age.
father is 4x= 4*8= 32.

NOW, in total 16 years is asked from the beginning,
So, sons age= 8+16= 24,
Fathers age= 32+16= 48,
48 is 2 times of 24!.

(4x+8) = 5/2(X+8).
= 8x+16 = 5x+40 how it came?

How 5/2 came? Can anyone explain.

How the ratio is 3:1?

It is 4:1 since in question it is clearly mentioned that "3 TIMES MORE THAN RONIT ".

Then only you'll get answer, never forget this if in question it says 3 times than another ratio will be 3:1, if it says 3 times more than or larger than other you should take 4:1.

Hot come 5/2? Please tell me.

Thanks for the explanation.