Aptitude - Problems on Ages - Discussion

Age n years ago means = x-n.
Let the ages of Kunal and Sagar 6 years ago be 6x and 5x years respectively.

Then, (6x+6)+4 = 11/(5x+6)+4 = 10.
Why you add the 6x+6, 5x+6.

@Fakrudin.

His son's age will be 15 year, please comment is am right or wrong. Thanks. If am wrong then please explain if I am right then I will be explain. Thanks.

The explanation given according to the question was absolutely right and i came to this conclusion after scratching my head for an hour. It has the logic. I represent the same model of question here under, both follows the same pattern.

Q: Five years hence the ages of Ram and his Son will be in the ratio 5:2. Three years ago, the ratio of their ages was 7:2. Find the present age of his son.

This would help you in clearing the doubts of this brain eating question.

Thanks.

Let Kunal's present age = x and Sagar's present age = y.

6 years ago, Kunal's age:Sagar's age = (x-6):(y-6).

Now ATQ, (x-6):(y-6) = 6:5,solving which we get equation as:5x-6y = -6. Lets consider it as eq.1.

Now again, after 4 years, Ratio will be (x+4):(y+4) which is given as 11:10.
Solving which we get equation as 10x-11y=4. Let it be eq.2.

Therefore the 2 eq. are,
5x-6y=-6. Eq.1.
10x-11y=4. Eq.2.

Multiplying Eq. 1 by 2,it is 10x-12y=-12.Let it be eq. 3.
Subtracting Eq. 3 by Eq. 2,

10x-11y-10x+12y=16.
Therefore y=16, i.e Sagar's age is 16 years.

I hope you all will get this.

These questions with their answers will play the crucial role to my ability.

Let present age of kunal and sagar is x and y. Now according to the question
six year ago the ratio of the ages of kunal and sagar was 6/5.

It means x-6/y-6=6/5. Now solve it and finally it is 5x-6y+6=0.....(1 equation).

Now four years after it means x+4/y+4=11/10. Now solve it and finally it is 10x -11y-4=0.....(2 equation).

Solve both equation 1 and 2. To solve firstly multiply the whole equation of 1 with 2 that is 10x-12y+12=0.

Now equate equation 1 and 2 that is 10x-11y-4=10x-12y+12. Finally y =16 which is the age of sagar at present.

I HOPE THIS SOLUTION WILL BE HELPFUL !

(m-6) = (n-6)(6/5) --> 1.
(m+4) = (n+4)(11/10) --> 2.

Equating, 'm' we get,
(n-6)(6/5) + 6 = (n+4)(11/10) - 4.

Then n = 16 = Sagar's age.

Six years ago means we have to deduct 6 from the current age but from the present age to after 4 years, they mentioned the ratio so.

From past 6 years we have to add 6 to come to present age and from present age we have to add 4. So total it will become like (x+6) i.e. is present and plus 4 i.e future.

So we get (x+6+4). Thats it.

6 years ago itself the ages are 6x, 5x respectively. Then hence 6 years it becomes 6x+6, 5x+6 right?

Why we have added 6 years instead of deducting as it is given that 6 years ago?