All questions tagged GMAT MathSkills IB - Consulting Q&A - PrepLounge.com

Hi Antonio,

I don't have experience about Bain, but I can talk for BCG.

- DIFFICULTY:

Quite challenging, however you don't have to make it 100% right in order to pass. The most important thing is to pay attention to time management.

- SUGGESTED PREP MATERIAL:

1) Keeping your math trained with GMAT exercises is always a good idea. Free resourced can be found online, for example:
http://www.mba.com/global/the-gmat-exam/prepare-for-the-gmat-exam/test-prep-materials/free-gmat-prep-software.aspx

2) Also tests that usually are for investment banks (with graphs analysis) are a useful. Free resourced can be found online, for example:
https://www.tptests.com/Candidate/practice/Instructions

3) Official BGC Potential test examples: https://www.bcg.com/careers/path/consulting/practice-interview-cases.aspx

Hi there,

I can share some useful materials with you for free.

Please feel free to reach me.

Best

Serhat

Hey,

There are a million ways to prepare for the GMAT! Especially given that you're excellent at the PST, I'm sure you just need a bit of guidance/practice on the GMAT before you do well. I'm not an expert on which GMAT resources are best, but a quick google and asking around should do the trick (I personally used Kaplan if that helps)

Hi Anonymous,

in general, the main issues with big numbers is forgetting zeros during operations. Potential tips to deal with big numbers are the following:

1. Use correctly 10^ powers in your math computation. For example 3.2B/723M can be transformed in 3200*10^6/732*10^6, which makes it easier to deal with math
2. Ask if it is fine to approximate. When you have to deal with math in market sizing, and sometimes even in business cases, you are allowed to approximate math to simplify the computation. In the previous example, for instance, you could transform the computation in 320*10^7/73*10^7, making the overall computation faster.
3. Keep good notes. One of the reasons people do mistakes with big numbers is that they don't keep their notes in order, thus forget/misreport numbers
4. Divide complex math in smaller logical steps. This is something you can use for big numbers after the application of the 10^ power mentioned above. If you have to compute (96*39)*10^6, you can divide the first element in 96*40 - 96*1 = 100*40 - 4*40 - 96*1 = 4000 – 160 – 100 + 4 = 3744*10^6
5. Use shortcuts for fractions. You can learn by heart fractions and thus speed up/simplify the computation - the most useful to know are 1/6, 1/7, 1/8, 1/9.

Hope this helps,
Francesco

Hi Anonymous,

basically here you have to compute

(1+x)^a=V

where you don’t know x and where a=5 and V=1,5.

For relative low interest rates and periods, the simpler process for precise results is the following:

1) Calculate what would be the solution with simple interest – in this case, 10%; the real result will always be lower than that

2) Decrease by 1 percentage point – in this case, 9%

3) Apply Taylor series till the third element. To do so, you would have to learn by heart the following formula:

1+ax+1/2*a*(a-1)*x^2

Given point 2, x=9%

1+0,45+1/2*5*4*0,09^2=

=1,45+10*0,0081=

=1,531

4) Repeat decreasing till when you find a value below V=1.5

Given x=8%

1+0,4+1/2*5*4*0,08^2=

=1,4+10*0,064=

=1,464

Thus the result is between 8% and 9%.

Hope this helps,

Francesco