Management Consulting Prep

Case Interview - Question types Case Interview Brain Teasers

From Management Consulting, to Wall Street, to even Google, Brain Teasers are one of (if not) the most popular as well as the most exciting types of interview questions. These questions often require thinking in unconventional ways.

  A quick glance

  1. Illusive Questions
  2. Visual-explanation Questions
  3. Wording Questions
  4. Pattern/Trend Questions
  5. Logical Questions

Brain Teasers!

Type No.1: Illusive questions

  How does it work?

  • While varying in formats and contexts, Illusive questions create illusions and draw your attention to insignificant details.

  What to do?

  • Realize the illusion and quickly identify the important details you overlooked at first sight. Resist the urge to quickly “fill in the blank”.

Test Yourself

  • Tracy’s mother had four children. One child was named April. The second one is May. The third is June. What‘s the fourth one’s name?
  • An electric train is traveling on a 2000-mile journey from Chicago, IL to Los Angeles, CA. It has 16 cars with a total of 320 passengers. The weather is cloudy and cool, with a warm front approaching from the south. Which direction will the steam blow?

It’s in the first sentence. Her name is Tracy.

There is no steam. It’s an electric train.

Type No.2: Visual-explanation questions

  How does it work?

  • Visual-explanation questions often provide you with weird and “impossible” situations and your task is to think of a story that “explains” all the facts.

  What to do?

  • Use a little creativity and imagination: Do not be afraid to tell “unordinary” story.

Test Yourself

  • A man is lying dead in the middle of a forest, in the middle of a puddle, in a scuba suit. How did he die?
  • A woman and a daughter walked into a restaurant. A man walked past and the women both said, “Hello, Father”. How is this possible?

A perfectly-accepted explanation is that he was swimming in a sea and a tornado picked him up and dropped him in the middle of a forest!

Either the man is a priest, or his name is Father!

Type No.3: Wording questions

  How does it work?

  • Wording questions use words with multiple meanings to trick your brain. With default interpretation (misled by the context), the question is impossible to answer.

  What to do?

  • Question your mind’s interpretation of every word in the question and in your thinking: “Is there any other alternative?”

Test Yourself

  • You walk across a bridge and you see a boat full of people yet there isn’t a single person on board. How is that possible?
  • What two words, when combined, hold the most letters?

The word “single” can mean not married. So the boat was full of married people.

Letters here can mean mails, so it is “post office”.

Type No.4: Pattern/ Trend questions

  How does it work?

  • Pattern/Trend questions  involve a series of numbers or letters with a certain pattern or trend. The questions then ask candidates to either identify the next item or to fill in a hole.

  What to do?

  • Think of a lot of possible trends, apply them into the string, and see if those trends correctly predict the string.

Test Yourself

  • What’s next in this series?   2 2 4 12 48 …
  • What’s the answer:   2 3 = 10

                                                   7 2 = 63

                                                   6 5 = 66

                                                   8 4 = 96

                                                    9 7 = …..

One possible trend is to take the previous number and multiply it with its position. So the next number would be 48 times 5, which equals 240.

144. Take the sum of the two and multiply by the first number.

Type No.5: Logical questions

  How does it work?

  What to do?

  • Use data analyzing skills to recognize the relationship between key facts and make inferences to solve the problem. (see also Hypothesis)

Test Yourself

  • During lunch hour a group of boys from Mr. Bryant’s homeroom visited a nearby grocery store. One of the five took an apple.

Jim said, “It was Hank or Tom”.

Hank said, “Neither Eddie nor I did it.”

Tom said, “Both of you are lying.”

Don said, “No, one of them is lying, the other is speaking the truth.”

Eddie said, “No, Don, that is not true.”

When Mr. Bryant was consulted, he said, “Three of these boys are always truthful but two will lie every time.”

Who took the apple?

From the data, we know that:

    • Two of the boys will always lie.
    • Tom’s argument logic is against that of Jim and Hank. If either of them is saying the truth, Tom is lying and vice versa. The same pair of counter logic applied with: Tom >< Don, Don >< Jim/Hank, Eddie >< Don.  They cannot be saying the truth at the same time.
    • Eddie’s statement can mean whether Jim and Hank are lying or they are telling the truth. The only possible scenario is the latter.
    • In the first case, it means Tom – Don – Eddie are all telling the truth which contradicts the logic (see above).

With deduction, the only possible scenario that fits the problem is:

    • Tom and Don are lying, which leads to Jim – Hank – Eddie are speaking the truth: “Hank and Tom are accused, Hank did not do it.”

Tom is the one who took the apple.

Type No.6: Wordplay questions

  How does it work?

  • Wordplay questions play with the organization, demonstration, and compositions of letters.

  What to do?

  • The key to these questions is to look at as many aspects as possible: synonyms, visual, verbal, etc.

Test Yourself

  • What does this represent?  COF FEE
  • What does this mean? gges egsg segg esgg

Coffee Break!

Scrambled Eggs!

Type No.7: Market-sizing / Guesstimate questions

Because of its popularity and importance, we have devoted an entire article covering it (see Market-sizing and Guesstimate). Go to the article for a detailed analysis of this question type.

What's next?

If you would like to see a whole eBook on Brain Teaser questions, you may want to join hundreds of candidates around the globe and get access to our Case Interview End-to-End Secrets Program!

If you’re ready to go deeper, explore our YouTube channel and subscribe to our mailing list for more great content! Start doing some extra practices for Brain Teasers today!

Share on facebook
Share on google
Share on twitter
Share on linkedin

Related Post

Leave a Reply

avatar
  Subscribe  
Notify of