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4 videos
2 skills
You are already familiar with calculating permutation ("How many ways could 7 different people sit in 4 different seats?"). But what if you didn't care about which seat they sat in? What if you just cared about which 4 people were in the car? Or put another way, you want to know how many combinations of 4 people can you stick in the car from a pool of 7 candidates. Or how many ways are there to choose 4 things from a pool of 7? Look no further than this tutorial to answer your questions.

Combination formula

VIDEO 11:17 minutes

Handshaking combinations

VIDEO 7:29 minutes

Example: 9 card hands

VIDEO 7:42 minutes
Thinking about how many ways we can construct a hand of 9 cards


Introductory combination problems

Permutations and combinations

Permutations and Combinations with overcounting