GMAT Club Forum & Discussion Board

COMBINATION and PROBABILITY - references.

If you have problems with combination and probability you can use this reference page to find information quickly.
I guess my small contribution to the GMATclub community will help other people to crack 800 score.

THEORY
-general:
Wiki Combination
Wiki Permutation
Wiki Probability
see also: http://gmatclub.com/forum/7-t10838


NOTES FROM WALKER

#1. Com-prob problems always have a few different solutions. Try to solve the problems in many ways, and that will give you self-reliance.

#2. Use enumeration of possibilities for the problems with complex restrictions.

#3. "How can I apply here C^n_k or P^n_k?" - is a wrong question. Always understand what the formulas mean.

LINKS

easy - 56860 - 6 boys and 4 girls
easy - 56779 - 10 red, 5 blue, 12 yellow pills.
easy - 56728 - 10 marbles contains 3 red marbles and 7 blue marbles
easy - 56446 - 4 people and integers between 1 and 4
easy - 56419 - an iced tea
easy - 55984 - a contest consists of n questions
easy - 55939 - 15 chess players
easy - 55734 - 3 candidates for a university
easy - 55689 - a pack of candy (2)
easy - 55644 - a five-question true/false section
easy - 55515 - a pack of candy
easy - 54481 - red and blue chips
medium - 58914 - a junior class has 1,000 students and a senior class has 800 students
medium - 58887 - that include Michael also include Anthony
medium - 58742 - 2 couples and 1person are seated in a row
medium - 58675 - n(n + 1)(n + 2) is divisible by 8
medium - 58670 - Probability of Winning
medium - 58640 - 4 people out of the 12 meried couples
medium - 58629 - two ineger sets
medium - 58609 - 9 people in the room
medium - 58529 - 2 objects collide on a cube
medium - 58521 - DS: heads than tails
medium - 58476 - Marco and Maria toss a coin three times
medium - 58360 - two ineger sets (2)
medium - 58357 - coin is flipped 5 times
medium - 58352 - 11 women and 9 men in a certain club
medium - 58350 - DS: 10 light bulbs
medium - 58233 - SQUARE
medium - 58187 - A certain company assigns employees to offices
medium - 58160 - 3 people are to be selected out of 8 people
medium - 58095 - Bob are among the 5 participants in a cycling race
medium - 58016 - 3 people is to be selected from 5 married couples
medium - 57997 - junior class has 1000 students and senior class has 800 students
medium - 57981 - positions at univeristy
medium - 57980 - women and men of 10 employees
medium - 57957 - rain on any given day in City X
medium - 57916 - a and b from a set of 4 consecutive integers
medium - 57882 - Anthony and Michael sit on the six-member board of directors for company X
medium - 57799 - A fair die is rolled once and a fair coin is flipped once
medium - 57695 - 3 dwarves and 3 Elves
medium - 57645 - A contest will consist of n questions
medium - 57629 - coin
medium - 57615 - A jar contains b black, w white, and r red marbles
medium - 57601 - GMPJBC
medium - 57577 - 5 people are to be seated around a circular table
medium - 57554 - Coach Miller
medium - 57332 - A coach will make 3 substitutions
medium - 56826 - 7 people and friendship
medium - 56814 - coin with sides marked heads and tails
medium - 56814 - tails side up more than five times
medium - 56812 - a election in Burghtown.
medium - 56709 - A set consist of 2n-1 element
medium - 56705 - 25 lines
medium - 56681 - 2 numbers from 1,2,3,4,5
medium - 56590 - 2 red and 3 blue marbles
medium - 56586 - different colors from 6 flowers.
medium - 56585 - 4 particular flowers of 8 different flowers
medium - 56572 - five-digit numbers
medium - 56557 - a committee of 4 distinct pairs of brothers and sisters
medium - 56556 - three letters taken from letters (a,a,b,b,c,c,d)
medium - 56530 - 12 playing cards
medium - 56530 - 4 cards of 12 cards
medium - 56446 - 4 people choose an integer between 1 and 4, inclusive.
medium - 56445 - 5 of 7 models
medium - 56443 - Two couples and one single person in a row of five chairs.
medium - 56349 - 3 girls and 4 boys in a row
medium - 56327 - shirts, shoes, pants
medium - 56122 - Six mobsters: Frankie behind Joey
medium - 56037 - a team from men and women
medium - 55870 - 3 cars
medium - 55823 - 4 senior partners and 6 junior partners
medium - 55811 - 5 women are in a race
medium - 55803 - a committee from 4 married couples
medium - 55764 - 100 numbered cubes
medium - 55743 - A and B stocks
medium - 55694 - Two fair dices
medium - 55673 - 3 different marbles
medium - 55644 - GMATT answers
medium - 55617 - 4 guys, 2 girls and 14 dogs.
medium - 55509 - A committee of 3 people from 4 couples
medium - 55504 - Ways from A to D
medium - 55472 - 4 pairs of brothers and sisters
medium - 55427 - 4 books fom 2 paperback and 6 hardback books
medium - 55421 - the probability that n(n+1)(n+2) will be divisible by 8
medium - 55413 - 3-digit integer
medium - 55410 - A committee from 5 military officers and 9 civilians.
medium - 55383 - 4 physics, 2 math and 3 chemistry books
medium - 55372 - My name is AJEET
medium - 55369 - 8 friends want to play doubles tennis
medium - 55366 - The most expensive two books
medium - 55340 - trhee letters from seven different postboxes
medium - 55311 - 6 cards
medium - 55253 - Rich has 3 green, 2 red and 3 blue balls in a bag
medium - 55141 - A bowl contains white and black balls.
medium - 55071 - 10 bottles of alcohol
medium - 55054 - 3 sniper's shoots
medium - 54794 - a fantasy football game
medium - 54650 - 6 cards
medium - 54332 - Bob and Jen in a race
medium - 53774 - The choir consists of 5 boys and 6 girls
medium - 50488 - 5 digit numbers
medium - 45753 - a committe of 3 of 6 people
medium - 41464 - deck contains 2 blue, 2 red, 2 yellow, and 2 green cards
medium - 19685 - 5 digit numbers formed using the digits 0, 1, 2, 3, 4, 5
medium - 15450 - A choir of 5 boys and 6 girls
medium - 15366 - Mary and Joe throw three dice each
medium - 59065 - A 4-letter code
hard - 58616 - PS Standard deviation + probabilities
hard - 57713 - the total number of permutations of n different things
hard - 57447 - A fair coin is tossed 10 times
hard - 57169 - DS: How many subordinates does Marcia Have



_______________________________________________

See also:

General:

http://www.gmatclub.com/wiki/Tests - Challenges (Online GMAT Tests)
http://gmatclub.com/wiki/GMAT_Study_Guide - GMAT Study Guide
1-t56014 - my GMAT timer


Math:

7-t44300 - good collection of Math links.
\tohttp://www.gmatclub.com/forum/7-t56486 - Combination-Permutation-Probability quant problems: my list with links
7-t57156 - Combination-Permutation-Probability quant problems: list of 55 different question with explanation [Amardeep Sharma]


Verbal:

11-t50635 - Brutal_SC, Idoms and good tips in Verbal section especially for non-native speakers [nervousgmat]
11-t28708 - A very nice thread of grammar use in GMAT with additional materials
http://www.manhattanreview.com/download ... -Guide.pdf - Manhattan Review Sentence Correction Guide
http://www.manhattanreview.com/download ... y-List.pdf - GMAT Vocabulary List – Basic Level
11-t4248 - SC-Tips [anandnk]

walker for president!

Thanks for it !

I add a link to your thread from Preatorian's one

new adds

new week updated

Dude, you the man!

I've finished with my P-C-P page. I'll add only interesting problems!
Good Luck!

Walker can you add this link to your P-C-P page. Excellent collection. Makes life so much easier for all of us.

I like the explanation you provided to this question.

7-t58742

watchout folks, walker is headed for the US presidency!

I'm just gathering some information for me and for you .....

yeah man..its awesome!

btw, when are u looking to take the test?

3-4 months. I have to SC

Thanks for the links!!!

Walker - awesome; simply awesome. Are you Walker as in Walker: Texas Ranger. Because if you are, a Chuck Norris reference comes to mind: "When Chuck Norris falls into water, he does not get wet. The water gets Chuck Norris."

Nice one man.

thanks walker it was just so awesome............wondering how many questions one can expect from P&C and probability....thanks!!

hey walker on question do you update this post...if yes then please let us know the frequency of updation of the post....thanks a lot for this wonderful work.....this is really so amazing....thanks!! again dude....good luck

Yeah, If you have interesting problems, post here links and I will add them to the list.

fantastic post.

walker flies.

awesome job walker!