Hey there,

Agree with Ken. The question is hard to answer without knowing your current performance and is also a bit misguided.

Some people practice 5 cases, then ace the interviews. Others do 100, then fail.

A few pointers:

• Focus on quality over quantity in everything you do (don't measure in hours but skills learned and proficiency achieved in a certain area) → only work with the best peers, case materials, and practice cases / drills
• Learn the right habits right from the start and take inventory: what are your strengths and weaknesses
• Create a detailed learning plan and execute against it. Constantly measure your progress and be brutally honest with yourself about where you need to improve
• Learn how a McKinsey case works: https://www.preplounge.com/en/articles/mckinsey-interview
• Learn what the PEI interview is and how you can prepare best: https://www.preplounge.com/en/articles/mckinsey-pei
• Instead of cases, base 80% of your prep on drills. Much more efficient and effective. This is also how you can work your quantitative reasoning muscle

A good coach can help you with all of these both as an efficiency and effectiveness multiplier. 

Check out my profile if you have any questions or want professional coaching. I have specialized in the McKinsey interviewing format and had tremendous success with my approach over the last 18 months.

Cheers,

Florian

Hi there, 

First of all, congrats on having so much time on your hands. It's truly a privilege. 

I would recommend you stick to at least four principles to make your prep as effective as possible:

1. Aim for quality over quantity - don't do a lot of cases, just make sure that you reflect on the ones that you do and take notes of what you learned and keep a log of your mistakes
2. Diversify your means of learning - use several methods so you get the best out of each one (paper-based, Youtube, audio, etc.)
3. Diversify your counterpart - aside from individual practice, do practice with other candidates (from all levels) as well as with coaches or other people who worked in consulting and can provide quality feedback
4. Mix different practices in one day - per day aim for a session with a counterpart, individual work, focus on numericals, watching videos, etc., to avoid boredom or diminishing returns.

As for maths, reach out to me for a free guide on how to get better at it. I doubled my computational speed in two months while preparing for my own interviews. 

Best of luck,

Hi there,

Great to see you're taking the time to prepare! Let's make sure you don't waste any of it. Unfortunately, this is what happens most of the time with self-guided study for McKinsey because the format is so unique and any prep material out there is usually very misleading in my opinion.

Hence, my short answer is to follow Florian's advice and make sure to get professional coaching from a former McKinsey interviewer. This will set you up for the most efficient and effective preparation.

The questions you ask are fair but they're not going to help you pass. There are many more dimensions to consider, most of which you're not aware of (and that's normal for any candidate).

Please get in touch if you'd like to discuss more. I used to be a McKinsey interviewer and know exactly what it takes.

It's hard to generalise not knowing anything about you and your current level.  It’s similar to muscle building, if you have the luxury of time (i.e., 50 days) I would encourage a case or two a day (say five times a week) where I would try to practice with someone for at least half of those cases.  To me, that sounds like plenty where your mental math should improve naturally if you're able to do so much.  Hopefully over time, you will have a clearer view (working with a coach helps here) of specific things you need to work on within the case that you can focus on as opposed to just running through the motions of a case.

Good luck!

(editiert)