Birthday Puzzle

On a new year day, two old friends (A and B) meet at a party. As they met after a long time person B wanted person A to guess his birthday. As both friends are not in touch for a long time person A was unable to guess his birthday. So person B decided to give some hints. Below are the hints:

  1. The day before yesterday I was 25 and next year I will be 28, then person B asked person A to find his birthday. 
  2. The above condition can be true for only one day in the year


Person B’s birthday is on December 31.


Person A met his old friend on New Year that is on January 1. So, the day before yesterday was December 30 at that time person B was 25 year old and at the present Day(January 1) B is 26 years old.

This year on December 31 person B will be of age 27 and next year his age will be 28.



December 30 25 years old
December 31 26 years old
January 1 (This year) 26 years old
December 31 (This year) 27 years old
December 31 (Next year) 28 years old

Therefore, Person B’s birthday is on December 31.

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