Casing Maths

Hi,

In interviews the aspect which causes more errors is pressure: start to solve calculations with strict time constraint. For longer formulas always share the calculation structure with interviewer before starting to write down the numbers: this helps to take time, to reduce the pressure and gives you the opportunity to receive a first feedback by the interviewer avoiding wrong calculations.

I recommend practicing with:

• Preplounge math tool: https://www.preplounge.com/en/mental-math.php
• Youtube channels with math tricks: https://www.youtube.com/playlist?list=PLjbxBzUM6SLlx_x8UABAdAB7Rbg9feqYa

Best,
Antonello

Hi there,

Q: I am still struggling with maths and calculations on the fly during a case. Any idea on how to improve/work on that?

It is difficult to answer without knowing what is the issue (eg struggling with formulas or with the math itself). 

You can find below some general tips.

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In terms of how to approach math during the case, this is what I would recommend:

1. Repeat the question – sometimes candidates do mistakes answering the wrong question
2. Ask for time and present how you would like to proceed from a theoretical point of view
3. Perform the math and present the interim steps to keep the interviewer aligned – don’t just say the final number
4. Continue with the math until you find the final answer
5. Propose the next steps on the basis of the results you found

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In terms of general math tips and avoiding mistakes, I would recommend the following:

1. Use correctly the power of 10. For example, 3.2B / 723M can be written as 3200*10^6 / 732*10^6
2. Ask if it is fine to approximate. You can ask the interviewer if you can approximate complex math. If allowed, this will help to solve simpler problems. In the previous example, you could get 320*10^7 / 70*10^7
3. Keep good notes. This helps to avoid to forget/misreport numbers
4. Divide complex math into multiple simpler steps. For example: (96*39)*10^6 → 96*40 - 96*1 = 100*40 - 4*40 - 96*1 = 4000 – 160 – 100 + 4 → 3744*10^6
5. Learn main fractions results. You can learn by heart fractions and speed up/simplify the computation - the most useful to know are 1/6 ~ 17%, 1/7 ~ 14%, 1/8 = 12.5%, 1/9 ~ 11%.

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I would also recommend to practice math under pressure - not just math. Many candidates are totally fine doing 67% of 67 in normal conditions, but freeze if asked this suddenly in a case interview.

In order to do so, try always to use a timer with a time constraint when you practice math – this will create pressure and help to replicate the actual conditions of the interview.

Hope this helps,

Francesco

Hi there,

there can be various root causes for poor case maths..

• Lacking quant foundations (arithmetics, % calc, algebra)
• Lack of conceptual understanding 
• Difficulties with multi-tasking (verbalizing while computing)
• Nervousness
• Etc

How you should approach fixing this, really depends on where your exact problem lies. 

Would need to understand a bit further your specific situation to advise on the best way to tackle this. Feel free to reach out via DM to discuss.

Hope this helps.

Regards, Andi

Hi there!

It mostly has to do with confidence. 

Confidence you build by seeing that you have successfully handled similar situations in the past. 

Which comes down to two things:

1. Actually having done those things in the past - you need to practice more and in the right way. 
   1. Technique is key. Reach out to me and I can share a guide that lays out the methodology that I use with my candidates for breaking down calculation problems.
2. Having a positive belief about having done them in the past - you need to change your limiting beliefs about your math skills.
   1. I've met lots of candidates with amazing background (e.g., top of their class Harvard MBA) who thought they were awful at maths. They weren't. They just always believed it and that held them back. If this is something you're struggling with, I'd suggest you get some expert support to help unlock it. 

Last but not least, it always get better with time. Across all the candidates I've worked with, I've never seen a person not improve as long as they were committed on getting better at math related questions.

Best,
Cristian

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Practicing for interviews? Check out my latest case based on a first-round MBB interview >>> SoyTechnologies  

1. Become really good at doing it on your own.

2. Significant exposure to an interviewer while doing maths, until it becomes second nature. You may need to add some stress elements to it (e.g. sometimes have an interviewer you don't know).

Hi,

This is also an area I struggled with in the past, given I studied an arts/humanities degree. 

I found that 2 things helped me:

1. Developing basic math mechanics (ability to do simple calculations under pressure) through rote practice
2. Developing proper understanding of key math concepts
3. Trying to simulate the pressurizing situation as much as possible (e.g. timing math drills, getting a practice partner to give me problems to solve etc).

All the best!

Hello,

I fully agree with Andi’s feedback here. Figure out the root cause first – what is it exactly that you find particularly challenging with case math? What specifically makes you nervous? If you let us know, we can suggest more specific advice to tackle this.

I love the math-drills and rocketblocks websites.

Hello!

Precisely for the high amount of questions (1) asked by my coachees and students and (2) present in this Q&A, I created the “Economic and Financial concepts for MBB interviews”, recently published in PrepLounge’s shop (https://www.preplounge.com/en/shop/prep-guide/economic_and_financial_concepts_for_mbb_interviews).

After +5 years of candidate coaching and university teaching, and after having seen hundreds of cases, I realized that the economic-related knowledge needed to master case interviews is not much, and not complex. However, you need to know where to focus! Hence, I created the guide that I wish I could have had, summarizing the most important economic and financial concepts needed to solve consulting cases, combining key concepts theorical reviews and a hands-on methodology with examples and ad-hoc practice cases.

It focuses on 4 core topics, divided in chapters (each of them ranked in scale of importance, to help you maximize your time in short preparations):

·        Economic concepts: Profitability equation, Break even, Valuation methods (economic, market and asset), Payback period, NPV and IRR, + 3 practice cases to put it all together in a practical way.

·        Financial concepts: Balance sheet, Income statement/P&L and Performance ratios (based on sales and based on investment), +1 practice case

·        Market structure & pricing: Market types, Perfect competition markets (demand and supply), Willingness to pay, Pricing approaches, Market segmentation and Price elasticity of demand, +1 practice case

·        Marketing and Customer Acquisition: Sales funnel, Key marketing metrics (CAC and CLV) and Churn, +1 practice case

Feel free to PM me for disccount codes for the guide, and I hope it helps you rock your interviews!