how long do you need to prepare for numerical reasoning tests?

So you're getting ready to face that numerical reasoning or data interpretation test for a consulting, banking or any other job that requires it. You think you're either not very good at these quantitative tests, or you're not sure how to prepare and how long to prepare.

People take different routes to preparation - some take many months, some take weeks. In general, the preparation effectiveness graph looks something like this:

Most people begin to mentally peak after a certain amount of time - it might change person-to-person, but often in intense preparations people peak in a few weeks. For those doing end-of-day preparations (like those preparing, say, for GMAT after work hours) it is in the range of 2-4 months. Many fail in their initial attempts and do better later, but in tests, especially job interview related tests, you might not have a second chance which is why strong preparation is essential.

It is therefore important to plan and execute on the test preparation. A 2 month plan, for example, might look like this

1. Basic test preparation

This is where you 'know all there is to know' about your tests. Doing GMAT? or some other CAT? or a consulting business judgment test (McKinsey, BCG, Monitor etc)? a bank test perhaps? an accounting test? (PwC, KPMG..). The key elements are

• Learn Format of the test - how is it administered? how long is it typically? how many questions? is there negative marking?
• Find out Content of the test - what is covered as part of the test curriculum? are you familiar with the content? to what extent should you prepare for the basics? It is purely numerical or data interpretation, or is there lot of algebra and geometry? are there inductive reasoning (picture series) questions?
• Prepare your basics - think you need practice on some basic areas? perhaps lots of algebra practice? perhaps just learning basic mathematics like addition, multiplication, division? Or more advance topics like understanding income statements, currency conversions, forex trading, short/long? read, practice all the necessary curriculum fundamentals in these days

2. Ramp-up phase

In this phase it's about picking up speed. This is an iterative process where you do a set of random tests that you can get your hands on, use some good prep material, discuss in online forums, learn problem solving strategies and apply them to your practice tests. The ramp-up phase should gear you up for the final, more intense pre-test preparatory days. You should end the ramp-up phase before peak with a couple of full-length, good quality practice tests (like, ahem, ours!) to put you in the final push mindset.

3. Peak Preparation

This is where you are armed with a series of tests, ready to be taken one or two every day until the day before the tests. You should aim to do these tests with solid focus

• Practice - choose a good time, a quiet location, do the test as if it were a real one
• Analyse - carefully analyse every answer, find out how you could have done the same question faster. Identify common traps and tricks you fell for, and list a couple of problem areas you want to focus on in the next test (for e.g. too much time on a test, falling victim to certain type of traps, weakness in a certain question area)
• Improvise - spend time before the next test on working on a few of the weaknesses. Now when you do the next test, be mindful of what you want to fix (accuracy, speed) and iterate

The day before test (or the series of tests in a week during recruitment season) you should stop, relax and go confidently to the test. Read our post on top 10 mistakes of numerical test takers to make sure you do not commit them! 

If you're in a recruiting season with several tests, you should finish your peak before the first and then each actual test will serve as practice. You can then do a few more new tests or repeat your practice pack.