That’s an interesting question and I guess it depends what you’re practicing for. Maths comes up a lot during the consulting recruitment process but in different formats. For instance, it could be as part of pre-interview numerical/data reasoning test or in the case interview. Improving your general mental maths can be beneficial for all aspects of the interview process. However, I would recommend taking a more tailored approach for each type too.
For general mental maths:
There are many ways you can improve your mental maths. This will be beneficial both for the entrance tests and for case studies. Some of the methods I found to be most beneficial include:
For entry tests:
Each company has their own style of test, it’s important to understand what the test is like before you start preparing for it.
For case studies:
Case study math refers to the calculations you are likely to encounter during a case interview. In order to prepare, I recommend the following:
Starting your math trained with GMAT exercises is always a good idea. The free resources can be found online, for example:
2) Also, tests that usually are for investment banks (with graphs analysis) are useful. For example:
If you need any further help or career advice, feel free to reach me out.
If you are talking about PST, I recommend the following approach:
1) Do 1 case from McK website in 60 min. Check your score. Target score is 22 out of 26 correct. If you do 17-18 correct you have great chances to improve in 3 days. If lower - reschedule the test.
2) Buy Viktor Cheng test prep program - best materials I've seen so far. Works also for express prep.
3) Do the 2nd test and check the score
4) Use other materials: GMAT IR and verbal parts, PST-like tests available online. The key thing - you should train to do them, fast
5) Do the 3rd test and check the results
If you want to improve your math skills for cases or tests in general:
1) Fast math - train, train, and train again
2) Critical Reasoning
3) Working with tables and graphs and deriving conclusions
4) Case math
Good luck with your interviews!
It depends on what you're preparing for: if it's for the pre-interview tests (e.g., PST, BCG online test, etc) that it can work as a proxy.
On the other hand, ff you are already preparing for the actual interviews, I found the math from GMAT to be much more difficult than the actual math in interviews (so I would say it's not really the best use of your time)