Hi,

Here is how you can improve your math skills:

**1) Mental math - train, train, and train again**

- Learn how to multiply double digit numbers (https://www.youtube.com/watch?v=6ndkkPZYJHo)
- Learn the division table up to 1/11 (i.e. 5/6 = 83.3)
- Learn how to work with zeros (Hint: 4000000 = 4*10ˆ6)
- Use math tools (Mimir math for iOS), Math tool on Viktor Cheng website to practice

**2) Critical Reasoning (for PST)**

- GMAT test CR and IR parts (Official guide and Manhattan prep)
- Mckinsey practice tests
- PST like tests from the web

**3) Working with tables and graphs and deriving conclusions**

- Study "Say it with Charts" book
- Check all available MBB presentations and publications. Practice to derive conclusions and check yourself with the actual ones from the article/presentation
- GMAT IR part (Official guide and Manhattan prep)
- Learn basic statistics (Any GMAT or MBA prep guides)

**4) Case math**

Practice common market sizing topics (Airport passenger flow, real estate volumes, subway passenger flows, car usage, etc.). You should become comfortable with making assumptions

Learn key financial topics (P&L and balance sheet and how to analyze them, Basic Valuation principles via NPV and comps) and case math:

- Interest rates calculations
- Compound margin
- NPV using the Rule of 72, Perperuity
- CAGR using the Rule of 72
- Currencies exchange calculations
- Speed, time, distance calculations
- Equations, systems of equations
- Ratio & Proportions
- Solving the problems by calculating the area of the triangle
- Profit / breakeven formula
- Correlations, outliers (being able to spot on the graphs, tables)

Good luck with your interviews!