In our Learn Logical Thinking and Programming Series -1, we are going to discuss about the below aptitude. This is one of the easiest logical thinking questions, usually asked in Aptitude rounds during interviews.


The sum of age of 5 children born at interval of 3 years each is 50 years. Find out Who is the youngest child?


let us assume that, 1st child will be x, 2nd child will be x+3, 3rd child will be x+6, 4th child will be x+9 and

5th child will be x+12.

The given Clue is -Sum of ages of 5 children = 50

Thus, we can say that x+x+3+x+6+x+9+x+12 = 50

i.e.., 5x+30 = 50

x = (50 – 30)/5, which is 4.

Now We will find this can be found using Java Program below.

Learn Logical Thinking through Programming:

public class YoungestChild {

public static void main(String[] args) {

int noOfchildren=5;

int age=50;

int interval=3;

int min=0;

for(int i=0;i<noOfchildren;i++)





System.out.println(“Youngest age:”+ min);




Youngest age: 4