The secret to have bulletproof mental math in just a few days
Bulletproof Mental Math is a short course that will give you the tools and practice to do effortless, error-free mental math in your case interviews
Don't let a simple math mistake get between you and the offer!
The type of math you need in consulting interviews is simple: adding, subtracting, multiplying and dividing.
You need to be able to do that with regular numbers, percentages and large numbers.
Straight forward, isn't it?
I'm pretty sure that if you're able to get an interview with a consulting firm, you can also do those operations.
So, why do people mess up with simple math?
If you've ever been to a case interview (or even done a mock interview), the answer is easy:
For the first time in your life, you're expected to do math quickly, accurately, under pressure, out loud and perhaps without even using paper.
School didn't prepare you for that.
(In fact, it prepared you for the opposite! Slow, quietly, pen-and-paper, and without a ton of pressure…)
And because of these nuances, candidates often make simple math mistakes in their cases that derail them completely.
See, interviewers won't outright reject you just because you made a small arithmetic mistake.
But they WILL reject you if you:
- Get so anxious from making a mistake (or getting stuck) that you tank your performance in the case from then on…
- Make tons of small math mistakes and never catch them, making them think the same would happen in the real job…
- Take so long fixing your math that you can't even get to the end of the case (that happened to me once)...
Because of this, learning to do error-free mental math quickly is a small but important part of your case interview preparation.
This means you'll want to learn this skill, but also do so without investing a lot of time!
How to rapidly improve your mental math skills
Most candidates I've met do some kind of mental math practice during their preparation.
They waste too much time.
They spend hours per week FOR MONTHS AND MONTHS practicing this skill.
And even after all that, they still can't rely on their skills.
In other words, the ROI is terrible.
Now, the reason this happens is because people work on this in a haphazard way.
- Download a mental math app to start practicing during the day
- Get a couple tips from a friend that improves things a little bit
- Apply those tips during cases, but keep making careless mistakes, wishing it to go away eventually
No wonder they don't improve that much…
What I've found over the years is that you can learn to effortlessly compute numbers in your head without making errors in just a few days, as long as you have a learning system with 3 things in place:
Let's break this down:
THING #1: Work ONLY on case-related math problems.
There are specific types of math operations that you'll need for your case interviews.
Some are very easy, so you just need to learn to be agile and to not make mistakes (e.g.: the 4 basic operations, percentages, operations with large numbers like millions and billions)
Some are a bit trickier, such as financial math and compounding, the Rule of 72, etc.
There are also many types of operations that you won't need: square and cubed roots, logarithms, etc.
If your focus is to improve your mental math for case interviews, it'd be wise to find use a method focused only on what you needed. You don't want any gaps, but you also don't want to waste time with difficult problems that won't be useful.
(This eliminates most mental math books, btw…)
One way to do that is to do "freestyle" practice – just practice your mental math as you do cases.
The only problem is that this misses the other two factors, so you're unlikely to improve that much unless you're already a "natural" on mental math.
THING #2: Learn ONLY the most effective mental math techniques.
Books focused on mental math do this well – they teach you specific techniques for computing numbers faster and without making mistakes.
Of course, they don't have as many practice problems and they teach you types of problems you'll never use in a case interview…
… Which is why you want a resource that gets the best techniques these books teach that apply to the problems you'll get in your cases.
We never learn these techniques in school, so it's no wonder we can't do mental math fast and free of error.
THING #3: Get plenty of practice!
This is the path many people take: they download a mental math app and churn out calculation after calculation in their downtime.
17 x 32
1,082 + 517
832 / 12
While this is better than doing nothing, you're not improving your technique to solve these problems, nor are you focusing on the right types of calculations.
You just do more and more math, and "try to get better next time".
At the end you're just tired, numb and frustrated.
Because none of these isolated solutions incorporate all three elements, candidates take months to improve their mental math skills.
Not to say, many still mess up even after all that practice.
But every candidate I have seen who have put these three things into place (the right problems, techniques and practice)...
… They all improve DRASTICALLY in a matter of days.
So far, no resource had this balance of these three things right for case interview prep.
This is why we've created Bulletproof Mental Math…