Hi there, Let me chime in here. First, try to think of this problem in terms of the expected value of the candidate drug: Expected Value = Likelihood of success * Present Value (in case of su... (more)

# All questions tagged case math - Consulting Q&A - PrepLounge.com

Ask a question## McKinsey Sample Case - Logic Question...

## Case Study Question: Market Size

Hello Sudipto, the first part of this case would be only about crunching the numbers, then you will need to add some hypothesis and finally make some considerations. ----> Crunch the numbers... (more)

## What is the best way to practice math for McKinsey quant heavy cases? Want to improve on all fronts - speed, accuracy and structuring questions especially when limited info is shared. Any advice would be appreciated! Thanks

Hi Jyotishman, as for structuring, the best preparation I found for math-intensive case has been on consulting handbooks of top MBA school. In particular, I would suggest the following: Downl... (more)

## Which is the most efficient way to multiply large numbers without losing track of zeros?

Sure, always use 10^power instead of zeros Example: 300x9000 = 3*10ˆ2 x 9*10ˆ3=3x9*10ˆ(2+3)=27*10ˆ5 Handwritten it looks not that complicated. If you get used to writing all the numbers that... (more)

## Maths for cases

Hi, Here is a set of things you need to know: 1) Math and formulas: Interest rates calculations Compound margin NPV using the Rule of 72, Perpetuity CAGR using the Rule of 72 Curre... (more)

## Tough math questions for McKinsey interview practice please?

Hi, Something that helped my candidates - download ALL casebooks available online and go through the math problems in the cases. They will give a good sense of required business terminology. Then y... (more)

## URGENT: Easy Math help needed

I would work backwards. But first, let's start with simple stuff. If the cost is €1 and the margin is 200%, this means that the sale price is €3 -> cost price x (1 + margin). So working backwards i... (more)

## When is it OK to estimate? Is a fast estimate better than a slow but accurate answer?

Hi, Ask the interviewer 1-2 times to get a sense of how comfortable he is with rounding numbers and how many zeroes he requires. Continue with an assumption that you should keep that level of... (more)

## Case Math Prep

Hi, Pls find below my list 1) Case math Practice common market sizing topics (Airport passenger flow, real estate volumes, subway passenger flows, car usage, etc.). You should become comforta... (more)

## How to divide and multiple thousands, milions and bilions fast?

Hi, There are several techniques that you can use: 1) Learn how to work with zeros. Best way - always use 10^power instead of zeros Example: 300x9000 = 3*10ˆ2 x 9*10ˆ3=3x9*10ˆ(2+3)=27*10ˆ... (more)

## Slow in parsing and digesting Math word problems at case interviews - how to improve?

Hi, Something that helped my candidates - download ALL casebooks available online and go through the math problems in the cases. They will give a good sense of required business terminology. Then y... (more)

I have started to make a list. Would appreciate if you can help me add to it! Market sizing... (more)

## How can I train my analytical analysis? (Which cases?)

Not a direct answer to your question, but make sure you are very comfortable with the math. 10-15 minutes/day on caseinterviewmath.com for example, will go a long way; this website will rank you per a... (more)

## Mental Math ressources

Hi, Basically, you need to develop 3 calculation skills: 1) Learn how to multiply double digit numbers (https://www.youtube.com/watch?v=6ndkkPZYJHo). 2) Learn how to work with zeros. Best way... (more)

## Math mistakes in interviews

Hi, It may be both. Or maybe he hasn't noticed the mistake himself. So just relax and keep fingers crossed. Best

## Request for a division table for percentage conversions

Hey there, I made the following quickly on Excel. However, I wouldn't advise you to try memorise the whole thing, as it's a) a lot to try remember and b) doesn't have that much value. Rather, memor... (more)

## Mental Math vs. Paper Math? At what level of difficulty is it OK to switch from mental math to paper?

I don't think there's any hard & fast rule. If I feel like the math is getting a little more complex, or I have too many numbers to keep track of, I always err on the side of caution: better go a... (more)