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How to answer brain-teaser interview questions

While you can't predict what interview questions you will be asked, you can prepare by developing a strategy for answering them.

Interview questions should be fair and designed to find out if you can do the job – but in reality, candidates can be asked some very odd things. While you can't predict what questions you will be asked, you can prepare by developing a strategy for answering them.

'Your answers might not reveal how well you will perform in the role – but they do give an indication of how well you cope under pressure and if you can think on your feet,' says John Lees, career coach and author of "Just the Job!".

What kind of questions can you expect?
Questions like "What are your strengths and weaknesses?" are difficult, but not surprising. Brain teaser questions tend to be unexpected and challenge you to think laterally. In theory, you could be asked anything, but certain roles attract particular types of questions.

'Some seemingly strange questions are actually related to the role, for example, "How would you sell me this water cooler?"' explain John. 'If you're going for a sales job or one that requires improvisation or quick thinking, the question is not totally unexpected.'

If the role demands quick approximation skills, don't be surprised if your maths skills are put to the test. This might be posed as a simple calculation or you could be asked something more lateral, like how many tennis balls fit into a Mini.

Interviewers often pose "what if?" questions which are entirely work-related.

John explains: 'So if you were up for a hotel receptionist job, you might well have to answer the question "How would you handle an angry customer who refuses to pay his bill?"'

Also be prepared for a seemingly throwaway question at the end of the interview. Questions like "What three things would you take to a desert island?" are designed to reveal something of your personality.

John says: 'As will all these type of questions, stay calm and give you answer along with your reasoning behind it – keeping it light and friendly.'

How to answer these questions
'The main skills being tested by brain-teaser questions are problem-solving and creative thinking – and while there's no right or wrong answer as such, there are good and bad ways to handle them,' says Rob Williams, a chartered occupational psychologist and author of "Brilliant Verbal Reasoning Tests".

'The most famous brain-teaser question is, "Why are man-hole covers round?" A good strategy is to rephrase the question. So try explaining, "Why aren't man-hole covers square or rectangular?"

Think about what would happen if you lifted the cover up, turned it sideways and dropped it diagonally through the hole. This actually gives you the answer since a round man-hole cover won't fall through its hole!'

Other types of brain teaser question are more open-ended.

'You might be asked for an estimate, but don't simply answer with a figure off the top of your head,' warns Rob. For example, if you were asked, "How many tennis balls could a Mini car carry?" Rob recommends using the following three steps to answer the question (which works for any sort of brain teaser question).

1. Repeat back the question slowly. Reflect upon each part of the question and give your immediate thoughts/ideas. Then you can go through saying how you are going to answer the question and why you have decided to do it that way.

2. Break the question down into parts then give an estimate of the number that would fit into a bucket. Then break down the different spaces in a Mini into say, front of car, back of car, in the boot, on the roof. Then all you have to do is to estimate how many buckets would fit into each of these four spaces.

3. Typically some clarification of the question will be allowed. This does not mean that you should criticise the question – or say that it is impossible to answer! What you will not be given is any guidance about how to answer or how "good" your answer is.

Some final tips to remember

– You are being tested on thinking creatively when put under pressure. Feel free to spend time thinking through your answer.

– Talk through your reasoning as you go since it is how you get to the answer and not the answer itself which is of interest to the interviewer. Any brain teaser question requires thinking through several stages of reasoning.

– It's thinking outside of the box that's needed so aim to come up with some unusual lines of thinking.

– Don't panic when you first hear a brain-teaser question. You have plenty of time to answer and after you think it through the question probably isn't as tricky as it sounds!

– If you do feel stuck then change your focus to probing your interviewer for more information on the question. Even if the interviewer refuses to give anything away, it is always worth showing that you have critical-thinking and creative-thinking skills.

Book links
Just the Job! by John Lees
Brilliant Verbal Reasoning Tests – Everything You Need to Know to Pass Verbal Reasoning Tests by Rob Williams

Image Copyright: america365, Shutterstock.com