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


[Combinatorics] | [Probability]

-general:
Wiki Combination
Wiki Permutation

-also:
7-t-10838.html
permutation-combinations-coverage-30315.html
permutations-order-matters-79661.html - how to distinguish Permutations from Combinations
-question collections:
pc-probability-download-57156.html

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 - 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://gmatclub.com/wiki/Tests - Challenges (Online GMAT Tests)
http://gmatclub.com/wiki/GMAT_Study_Guide - GMAT Study Guide
1-gmat-timer-56014.html - my GMAT timer


Math:

7-t-44300.html - good collection of Math links.
\tohttp://gmatclub.com/forum/7-t-56486.html - Combination-Permutation-Probability quant problems: my list with links
7-t-57156.html - Combination-Permutation-Probability quant problems: list of 55 different question with explanation [Amardeep Sharma]


Verbal:

11-t-50635.html - Brutal_SC, Idoms and good tips in Verbal section especially for non-native speakers [nervousgmat]
11-t-28708.html - A very nice thread of grammar use in GMAT with additional materials
http://manhattanreview.com/download/MR- ... -Guide.pdf - Manhattan Review Sentence Correction Guide
http://manhattanreview.com/download/GMA ... y-List.pdf - GMAT Vocabulary List – Basic Level
11-t-4248.html - SC-Tips [anandnk]

Additional Practice Questions:

Medium - 79490 - How many four-digit odd numbers do not use any digit more than once
Meidum - 79312 - A jar contains only x black balls and y white balls

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.

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

fantastic post.

walker flies.

awesome job walker!

Thanks!

I add "NOTES FROM WALKER" to my first post for new members

Thnx Dude. You ROCK.