Aptitude - Problems on Ages - Discussion

A man had three sons and they were born at an interval of five years. The sum of their ages after 5years will be 60 years. What was the age of youngest son five years ago?

Can anyone solve this?

There is a slight change they should have mention let the youngest child be x.

Then, x + (x + 3) + (x + 6) + (x + 9) + (x + 12) = 50,
5x = 20,
x = 4.

Age of the youngest child = x = 4 years.

Can anybody solve the problem? Please.

Three times the present age of a father is equal to eight times the present of his son. Eight years hence the father will twice as old as his son at that time. What are their present age?

Why are you taking odd ones?

Hi guys,

The best easy way to solve this type of question : You can go as per options and we can reduce the time consumption.

Go as per 1st option : for 1st child if 4 years then 2nd child 4+3 =7 years, Similarly 3rd child 10 years, 4th child 13 years and 5th child 16 years.
Then,
Add all the years if u get total 50 years (given in question) you decide your answer is correct. No need to calculate we can reduce our time for this type of easy question.

@Nikil,

The sum of ages of 5 children and their difference is 3 years.

We consider that 1st children age be "x".

Then the second one be "x + 3".

3rd one be"x + 6".

4th one be "x + 9".

5th one be "x + 12" (because they all are born with three years difference).

How we get x + 12?

Explain this step.

Average/total number.

A + B + C + D + E/5 = 50.
50/5 = 10.
C = 10.
10 - 3 = 7.

7 - 3 = 4 -> YOUNGEST ONE'S AGE IS 4yrs.

5x + (3 + 6 + 9 + 12) = 50.

5x + 30 = 50.
5x = 50 - 30.
5x = 20.

x = 4.

If we consider the age of younger child x then after 3 years that child will (x + 3) again 3 years 2nd child born and he become (x + 6) like this up to date the child become (x + 12).

Then the age of younger brother should (x + 12) not only x.

Means answer should be (4 + 12). i.e =16.

Then why not getting 4 as the answer. Can anyone explain it?