This brief video covers the core technique of how I do almost all probability questions and shows the two most common mistakes I have seen students make over almost a decade of tutoring.
I offer private GRE / GMAT tutoring online at a fixed rate of $140/hr. Please get in touch via the email below, or through my tutoring website: www.gretutorlondon.com/
Enquiries: philip@gretutorlondon.com
Here are three different examples or probability questions that might appear on the GRE or GMAT.
There are 3 red beads and 5 green beads in a bag. If two beads are picked at random and without replacement from the bag, what is the probability that both beads are green?
You need to know the letter technique.
There are 3 red beads and 5 green beads in a bag. If two beads are picked at random and without replacement from the bag, what is the probability that both beads are the same colour?
The difference between AND and OR in probability.
There are 3 red beads and 5 green beads in a bag. If two beads are picked at random and without replacement from the bag, what is the probability that the two beads chosen are different in colour?
You cannot neglect the order in probability. That’s why the Letter Technique is so important.
These techniques help for GRE probability, which comes up only occasionally, and GMAT probability, which comes up all the time at the higher level.
These examples help for the without replacement scenarios but are also applicable to the with replacement ones too. This is not advanced probability but a solid intro to quant probability and probability on the GRE and GMAT. It is an 11-minute answer of ‘how to do probability’. I will be very satisfied if, after watching this introduction to probability, you avoid these two common probability mistakes.
I offer private GRE / GMAT tutoring online at a fixed rate of $140/hr. Please get in touch via the email below, or through my tutoring website: www.gretutorlondon.com/
Enquiries: philip@gretutorlondon.com If you’re now ready to get into your dream MBA program, my former student, Angel, is offering virtual private Admissions coaching. She was admitted into Harvard Business School, The Wharton School of Business, and Columbia Business School (accepted into every school she interviewed for) after graduating from UCLA with a degree in Communication. She also got 3 perfect scores on the GRE’s Analytical Writing Assessment (99th percentile).
Here is her link - linktr.ee/angel_accel - and you can reach her at angellinzhu@gmail.com with the subject line, “PHILIP SENT ME.”