7 of the Hardest Interview Questions Ever Asked
December 30, 2020
Based on the Quora thread: What is the toughest question ever asked in any interview?
Obviously, interviewing is important. It’s your chance to get to know the candidate and really decide if they are what you’re looking for in the position.
That said, some organizations have taken it too far, asking impossibly difficult questions to see how someone can handle pressure. Google, for instance, was infamous for asking ridiculously tough brain teasers, only to put an end to such questions several years ago.
So, what are some of the hardest interview questions ever asked?
1. There are infinite black and white dots on a plane. Prove that the distance between one black dot and one white dot is one unit.
A question asked during an interview for a technology analysts role at Goldman Sachs. If you know the answer, you probably should be working for NASA.
2. Can you tell me the 15 errors in the code you just created?
The following scenario unfolded at an interview with one of the computer giants:
A candidate for a software engineering position walked into an interview and was asked to write a program that prints “Hello World” in any language. The interviewer glanced at the code and told the candidate he had five minutes to find 15 errors in the code.
The candidate couldn’t do it and was rejected for the job.
3. How can you drop two eggs the fewest amount of times, without them breaking?
A rather long-winded question, asked by a Silicon Valley engineering company. Here’s the full question:
Suppose that there is a building with 100 floors. You are given two identical eggs. The most interesting property of the eggs is that every egg has its own “threshold” floor. Let’s call that floor N. What this means is that the egg will not break when dropped from any floor below floor N, but the egg will definitely break from any floor above floor N, including floor N itself.
For example, if the property of the eggs is that N equals 15, those eggs will always break on any floor higher than or equal to the 15th floor, but those eggs will never break on any floor below floor 15. The same holds true for the other egg, since they are identical.
Here is the question: What strategy should be taken in order to minimize the number of egg drops used to find floor N (the threshold floor) for the egg? Also, what is the minimum number of drops for the worst case using this strategy?
4. What has changed in this room since you walked in?
A candidate walked into an office for an interview and was asked by the interviewer what their biggest strength was. The candidate said they have great attention to detail.
So, the interviewer told the candidate to leave the office and come back in in five minutes. When the candidate did, the interviewer asked him what had changed since when the candidate first entered the room.
The candidate didn’t know.
The answer? The hands on the clock had moved.
5. Prove to me that you're honest — in one minute.
Here's an example of another one of the hardest interview questions we came across: an interviewer asked a candidate if they're honest and the candidate said yes. The interviewer said prove it to me — in one minute.
The candidate was speechless.
6. How many stairs did you come across in this building while you were on your way to this interview?
Asked in an interview with an engineering company. We're not sure if that's one of the hardest interview questions ever asked, or just plain impossible.
7. When do things move faster? Day or night?
A candidate was asked this during an interview to get into a university’s engineering program. The candidate said night, with the interviewer following up with why.
"Because there’s less traffic at night," the candidate said. The interviewer was not amused.
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