Basic Concept for problems on ages

Basic Concept for problems on ages :

#1. If the present age of ‘A’ is ‘x’ years, then

‘n’ years ago => Age of ‘A’ was (x-n) years.

‘n’ years after => Age of ‘A’ will be (x+n) years.

#2. In general, at the starting of the solution we have to assume the present age of one person. It is better to assume the present age = ‘x’ years.

#3. So I advise you to assume the age of the younger person = ‘x’ years.

#4. If the present age ‘A’ and ‘B’ are ‘x’ and ‘y’ years respectively, then

‘n’ years ago => Age of ‘A’ and ‘B’ were (x-n) and (y-n) years respectively.

‘n’ years after => Age of ‘A’ and ‘B’ will be (x+n) and (y+n) years respectively.

#5. The age difference between you and your friend is let’s suppose 6 years. And after 10 or 15 years this will be same, because clock will run equally for both of you. I hope you are getting what I am trying to say. : )

Q 1. Lina got married 8 years ago. Today her age is 9/7 time her age at the time of her marriage. At present her daughter’s age is 1/6 of her age. What was her daughter’s age 3 years ago?     (PNB MT 2009)

Explanation:

Let’s assume present age of Lina = x yrs.

Hence,  x = (x-8) * 9/7 => x=36 years.

So present age of daughter = 1/6 * 36 => 6 years.

3 years age of daughter = 6-3 = 3 years.