7 Tough Brainteasers To Assess An Interviewee's Critical Thinking [SlideShare]

Bored of asking the same old, predictable interview questions? Want to try something new? Brainteasers could be the answer! Check out this SlideShare to find out more.

June 20, 2023

I'm not a fan of brainteasers.

From my experience, most candidates (especially the really, really good ones) find them unnecessary, overcomplicated and just a little bit silly.

In fact, we actually condemned them in a recent blog post: 5 Pointless Interview Questions.

So... why the hell have I created this SlideShare? (Good question...)

Well, just because they aren't right for my business, doesn't mean they aren't right for yours!

So this week, I'm breaking down brainteasers, to give you a chance to make a more informed decision and decide whether you can make them work...

7 Tough Brainteasers


Slide Transcript

Slide 1.

7 Tough Brainteasers to Test an Interviewee's Critical Thinking.

Could (and should) you use brainteasers to suss out your bright sparks?

Slide 2.

Why use brainteasers?

  • Problem Solving. Can they at least attempt to solve problems as they arise?
  • Analysis. Can they look at the big picture and analyse all the information to find a solution?
  • Creativity. Do they think outside the box?
  • Performance under pressure. Can they keep it together, when faced with the unknown?

Slide 3.

Asking questions that have no relevance seems like a great idea…right?

Slide 4.

Q1. “If you were a pizza delivery man, how would you benefit from scissors?” Apple Inc.

Slide 5.

A2: There is no right answer! But….

Slide 6.

There are certainly good signs…

A candidate who deliberates and comes up with a remotely relevant answer and explains their reasoning…

What is it like to be a pizza delivery man? How will those scissors come in handy?

Clever sods might even give reasons why you shouldn’t take scissors, turning your question on its head.

Slide 7.

And bad signs…

  • Candidates who won’t answer the question! It’s an interview…YOU make the rules.
  • Candidates who can’t answer the question! Where’s the creativity?

Slide 8.

Q2. An apple costs 40 cents, a banana costs 60 cents and a grapefruit costs 80 cents. How much does a pear cost? Epic Systems

Slide 9.

Did you get the right answer?

Slide 10.

Take another look…

“An apple costs 40 cents, a banana 60 cents and a grapefruit costs 80 cents. How much does a pear cost?”

Slide 11.

A2: It’s all about the vowels. If each vowel is worth 20 cents, then the apple would be worth 40 cents, the banana would be worth 60 cents and the grapefruit would be worth 80 cents.

Slide 12.

If a candidate answers correctly, in such a high- pressure situation, you should be impressed…

Slide 13.

However… Don’t be too quick to judge! Surely there are other answers that could impress you?

Slide 14.

Other Good Signs…

Is their answer sensible, thought-out and practical?

Slide 15.

Bad Signs…

Blurting out an answer without fully considering the consequences could give you a little hint about how they’ll make decisions in the future…

Slide 16.

Q3: How would you test a calculator? IBM

Slide 17.

A3: There is no right answer! (But there’s plenty of wrong ones!)

Slide 18.

Good Signs:

Anyone who offers a method that is…

  • Strategic
  • Detailed
  • Efficient
  • Systematic

…and that would actually work!

Slide 19.

Bad Signs…

Anyone who offers a method that is…

  • Thoughtless
  • Unjustified
  • Impossible
  • Confused

What does this tell you about their general organisational skills?

Slide 20.

Q4: “A farmer needs to cross the river with his chicken, a sack of corn and a fox. His boat unfortunately only fits himself and one other item. If he leaves the fox with the chicken, the chicken will get eaten, whilst if he leaves the chicken with the corn, the corn will get eaten. How will the man get safely across with all 3?"

Slide 21.

It’s easy when you know how…

Slide 22.

A4: The man takes the chicken across and then goes back for the fox. He can’t leave the fox and chicken together so when he drops the fox off, he picks up the chicken. He then goes back for the corn. He can’t leave the corn and the chicken together so when he picks up the corn, he drops off the chicken. When the corn is safely with the fox on the right side of the river, he goes to collect the chicken. “

Slide 23.

The REAL question..?

Slide 24.

Why’s the farmer hanging out with a fox in the first place?

Slide 25.

Other Good Signs…

If you use the question as a team activity during a group interview or assessment day you can look out for…

  • Leadership Skills
  • Team Work Skills
  • Interpersonal Skills

…look out for those who sensitively facilitate the successful completion of the task.

Slide 26.

Bad Signs…

  • Misunderstanding the question
  • Reaching the wrong conclusion
  • Sacrificing the wolf or the chicken

Beware of candidates who’ve heard it all before!

Slide 27.

Q5. “How many potatoes (in kg) does McDonald’s sell in a year in the UK?” Oliver Wyman

Slide 28.

A5. 200 Million KG (Roughly)

Slide 29.

There are loads of variations on this question…

How many square feet of pizza are eaten in the UK every year?

How many petrol stations are there in the UK?

How many pennies, if placed on top of each other, would it take to reach the top of Big Ben?

Slide 30.

Good Signs…

  • Any candidate whose answer is remotely close!
  • Sensible presumptions
  • Evidence of mathematical ability

Slide 31.

Bad Signs…

Incorrect mathematical sums, hasty deductions and unreasonable reasoning…

If you actually care about their numerical reasoning capabilities that is…

Slide 32.

Q6. Tracy’s mum had 4 children. The first child was named April, the second was named May, the third June. What was the 4th child called?

Slide 33.

Did you notice the cheeky little trick? Look again…

Slide 34.

“Tracy’s mother had 4 children. The first child was named April, the second was named May, the third June. What was the 4th child called?”

Slide 35.


Slide 36.

Bad Signs…

Anyone who incorrectly answers the question!

Slide 37.

Ok ok… that’s a bit harsh.

We’ve all had those complete mind-blank moments in the past!

If your candidate is struggling under the pressure, give them a little hint - re- state the question!

Slide 38.

Q7. How do you know if the light in the fridge is on or off when the door’s closed?

Slide 39.

A7. There is no right answer!

Slide 40.

You could…

  • Use a camera
  • Drill a hole in the fridge
  • Find the sensor and test it with your thumb
  • Touch the light bulb (carefully)

Be creative and the list is endless…

Slide 41.

Bad Signs…

No answer at all implies a sincere lack of creativity!

Slide 42.

So…when should I use brainteasers?

Slide 43.

At any stage of the interviewing process!

From telephone and face-to-face to panel and Skype but they’re most effective during the… Group Interviews

Slide 44.


Brainteasers are the most difficult questions to answer during an interviewer.

(So much pressure…so little time!)

Slide 45.

Even great candidates might get put off and completely fudge the answer up!

Slide 46.

At Coburg Banks, we prefer a mixture of…

Click on the links above to find examples for you to swipe and deploy in your own interviews!

Slide 47.

Click here to sign up to our Recruitment Blog with…

  • Cutting-edge guidance, revealing how to attract and retain the best candidates, without wasting precious time on inappropriate ones.
  • More insider secrets revealing how to draw out the best (and the worst) in your interviewing candidates.
  • Shocking and embarrassing true confessions from recruiters across the globe; we’ve all made mistakes, now you can learn from them!

Slide 48.

Enjoy and Good Luck from the Coburg Banks Team!

Want to read more?

Check out these great articles, revealing a little bit more about brainteasers...

Good luck!

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