In this post we will delve deeper into McKinsey and it’s recruitment process. Today we will discuss the McKinsey Problem Solving Test or PST. We already explored the history of McKinsey and later this week we will dive into the specifics of their case interviewing methods. But today it’s all about the McKinsey Problem Solving Test: a multiple choice test that is really a pen-and-paper case interview in sixty minutes (70 minutes for non-native speakers as the test is in English only).
Originally developed to help streamline the application process and reduce the burden on actual consultants (read: billable hours) giving case interviews to hopeless candidates. Since there are thousands of McKinsey applicants worldwide in any given year, the PST has evolved as a thoroughly tested selection tool with high predictive capabilities. If a candidate passes the McKinsey Problem Solving Test, his or her chances to ace the case interview are also considerably higher. On the other hand, if you fail the PST you will have a hard time convincing McKinsey that you should be allowed to pass to the next round: the McKinsey Problem Solving Test features a true cut-off score: if you don’t make it, you’re out.
The McKinsey PST
So, what is the PST all about? It consists of about 25 questions based on five or six cases. Every case starts with a short description of the company, some data on revenues or number of employees. Maybe a chart on how profit has evolved through the years. At the end, there’s often a quote of the CEO or manager that has hired you with the question they want you to solve. Then there are about 5 questions about the case, either based on the info in the introduction or some new piece of data (a table, a chart) followed by a question. When I took the McKinsey Problem Solving Test for example, there was a case about a fish restaurant who served three kinds of fresh fish. The first question was about some piece of information hidden in the introduction. After the fourth question, a new problem was introduced, as the chef wanted to buy an automatic shrimp peeler and wondered whether it was worth the investment. The final two questions were on that new problem.
What do you need to do to pass the McKinsey Problem Solving Test? First of all, you need to read both quickly and carefully. Secondly, you need to polish up your math: the PST will always feature some quantitative questions. And finally: practice, practice, practice!
Skim the introduction and underline important data or observations. Read the question very carefully. For example, the first question in the fish restaurant case was (along the lines of):
“What is the objective of the restaurant owner?”
You then go back to the introduction, in which the owner is quoted (a piece of info you should have underlined), saying: “I want to reduce the amount of fresh fish per plate so I can reduce prices and attract more customers”. Now pick the best answer:
- The owner’s goal is to reduce prices.
- The owner’s goal is to reduce cost.
- The owner’s goal is to increase profit.
- The owner’s goal is to increase the amount of sales.
All of the above are right, or a logical result of the actions of the owner. The best answer however, is D: as the goal of the owner is to increase the amount of customers. Maybe the answer surprises you, but take this piece of advice: during your interviewing process and while taking the PST you’ll have to think as a consultant. Often the client requests a certain analysis or asks for a certain problem to be solved that is not really the problem. Many times you’ll have to rephrase the client’s question and drive down to the real problem they face. Consulting firms look for this skill in candidates, and it’s no surprise these questions also turn up in the PST. Another thing you could do is to read the questions first so you know what is important, before you read the ‘real’ info. Since you only have a limited amount of time, you don’t want to waste time while trying to figure out the exact meaning of a graph or table.
While you are not allowed to bring a calculator, the McKinsey Problem Solving Test features some quantitative questions as well. It’s designed to give candidates with all backgrounds (non-business ones as well) an even chance, so don’t expect NPV calculations or the like. But the calculations are both tough and time-consuming: remember that you have only 60 or 70 minutes to finish the test. It does help to brush up your math, so check this post on case interview math. Being able to calculate out of your head quickly and accurately is beneficial both during your McKinsey Problem Solving Test and your real case interviews and is one of those things you can get really good at with daily practice. It’s like training a muscle: it needs patience and practice, so get started as soon as possible.
Practice makes perfect, but there is very little material online that compares to the real McKinsey Problem Solving Test. You can use the previous McKinsey PST from their website, use PST-like tests from firms started by McKinsey alumni or practice by making the storyline questions in GRE-books.
All of them are either not very much like the ‘real’ PST or give you very little insight into the tactics you can employ to maximize your score on the PST. Every bit of practice helps, which is why you can download these practice materials for free below. But if you want to learn how to ace the Problem Solving Test with confidence, with a full practice PST to put your skills to the test, I suggest taking a look at “The Key to the PST”, which includes inside info on how to prepare and a full Practice PST with a detailed answer guide to learn from your mistakes.
I wrote the book because a friend of mine who had to take the PST really liked the section on PST-preparation in my other book, “Cracking the Case“. He asked me to write a full sample test and I walked him through the test and his answers. After he successfully took his PST, he urged me to put the sample test I wrote online so others could practice with it as well. I decided to add the full PST-preparation section from “Cracking the Case” to the sample test, as well as a detailed answer guide (I can’t walk you through your answers personally, unfortunately). Since putting it online in June 2012, hundreds have downloaded “The Key to the PST” to help prepare for their test.
Not sure why you would need to practice? One of the readers of my book experienced first hand why practice helps:
I recently used your book to prepare for the cases. It was really helpful. I have just gotten news that I passed the test and the wonderful thing is I managed to finish with some 10 minutes to spare and revise the bits I was unsure of. Your guide really helped. Thanks again.
You can get it now for just $17, just click to buy it now or click here for more info. Don’t want to spend any money yet? You can also use the material I gathered below: it’s free. Everything I’ve gathered over the years is free to download and to use as you like:
But if you want inside information on how to ace the PST, including a complete practice PST with detailed answer guide, I advise you to take a look at my book on the subject. “The Key to the PST” is available now for just $17! Click for more info.
Good luck with your PST!
Update: A reader pointed me to some other great resources:
Another good way to practice is using GRE training materials, especially the story-line questions. Below are links to three GRE books:
And also some free practice online: