Summary of permutations, combinations and probability
Last updated: 24 Nov 2008
You should remember the following
- Permutations
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Permutations are where order does matter
- Combinations
- Combinations are where order does not matter
- Basic rule of probability
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When each possibility is equally likely.
- 'And' probabilities
- The probability of two independent outcomes both occurring can be found by multiplying their individual probabilities together.
- 'Or' probabilities
- The probability that either of two exclusive outcomes will occur can be found by adding their individual probabilities together.
Further reading
If you found any part of this tutorial difficult then you may want to study further.
- Probablity lesson from the GMATClub.com
- GMAT probability in perspective from GMAT Daily Tips
- Probability from Math Goodies