Brain Teaser Interview Questions

Brain teaser or puzzle interview questions are sometimes used when interviewing candidates for high-tech, engineering, and other analytical types of positions. Here's an example of a brain teaser question.

"A line of 100 airline passengers is waiting to board a plane. they each hold a ticket to one of the 100 seats on that flight. (for convenience, let's say that the nth passenger in line has a ticket for the seat number n.)

Unfortunately, the first person in line is crazy, and will ignore the seat number on their ticket, picking a random seat to occupy. all of the other passengers are quite normal, and will go to their proper seat unless it is already occupied. if it is occupied, they will then find a free seat to sit in, at random.

What is the probability that the last (100th) person to board the plane will sit in their proper seat (#100)?"

So what does this have to do with the position the candidate is interviewing for? According to a recent article in Business 2.0, high-tech companies like Google and Microsoft and other well known companies such as Amazon are using puzzle or brain teaser questions to source top talent and determine their problem solving skills. By asking these types of questions the interviewer may be able to better gage the candidates ability to make educated guesses, which is a critical skill for professionals in these lines of work.

According to the 2007 Career Industry Mega Trends report conducted by Career Directors International, eight percent of human resource professionals surveyed said they used puzzle interview questions. If you are interested in learning more about brain teaser questions, take a look at the TechInterview website. And when you figure out the probability of the 100th person sitting in their proper seat, let us know the answer!