Brain Teasers - Barbershop

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Difficulty: Intermediate | Style: Brain Teaser | Topics: Brain teaser

Problem Definition


A business man is in a village for a meeting. He has time to spare before the meeting, so he decides to get a haircut. He looks at a street map and was surprised to find that there are only two barbers in town, right across the road from each other.

He went into the first one and was shocked by the dirtiness and the hair everywhere. The place was a mess! He looked at the barber and the barber had a really messy haircut, all in his face and uneven. He went across the street to the other barber and saw the place was immaculate, clean and shining like new. The barber was nicely dressed and had a dazzling haircut: it was perfect. However, the man walked across the street and got his haircut at the shabby barbers.




Two rivalling islands Blueria and Redania have ever since been fighting about what the best color is. The only connection between the islands is a bridge, which is guarded by a security guard on the Redanian side, who would come out every three minutes and check on the bridge. He has instructions to deny access to everyone coming from Blueria and spray everyone with red paint who is trying to escape from Redania to Blueria.

A Redanian woman that loves the colour Blue desperately wants to live in Blueria. Being covered in red paint is not an option. She knows that she will at least need six minutes to walk across the bridge.

How did she manage to live in Blueria?


Brain Teasers are short questions with difficult logical or creative answers. They are a good way to test your analytical skills and capacity to think out of the box. These short questions also show the interviewer your ability to elaborate on difficult tasks from the real world. Each Brain Teaser is supposed to be solved by the interviewee in about 5-10 minutes.

If the interviewee gets stuck in a brain teaser (i.e. spends more than 10 minutes), propose to go on to the next one.

Detailed Solution


Since people can't cut their own hair and there were only two barbers in town, the two barbers must have cut each other's hair. So, the poor haircut must have been performed by the clean barber. Therefore, the good haircut must have been performed by the messy barber in the first shop.


She walked on the bridge towards Blueria for 3 minutes and just as the guard was about to come out, she turned around walking back to Redania. The guard saw her and sent her back (or what the guard thought was back) to Blueria. In her case it was the very island she wanted to go to.

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