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Probability using combinatorics

14 videos
1 skill
This tutorial will apply the permutation and combination tools you learned in the last tutorial to problems of probability. You'll finally learn that there may be better "investments" than poring all your money into the Powerball Lottery.

Example: Probability through counting outcomes

VIDEO 2:09 minutes
The probability of getting exactly 2 heads when flipping three coins. Thinking about this by visualy depicting all of the outcomes.

Example: All the ways you can flip a coin

VIDEO 2:14 minutes
Manually going through the combinatorics to determine the probability of an event occuring

Getting exactly two heads (combinatorics)

VIDEO 10:00 minutes
A different way to think about the probability of getting 2 heads in 4 flips

Probability and combinations (part 2)

VIDEO 10:36 minutes
Making at least 3 out of 5 free throws.

Probability using combinations

VIDEO 9:10 minutes
Probability of getting exactly 3 heads in 8 flips of a fair coin.

Exactly three heads in five flips

VIDEO 6:51 minutes
Probability of exactly 3 heads in 5 flips using combinations

Example: Different ways to pick officers

VIDEO 2:23 minutes
Thinking about the different ways we can pick officers in order to find the probability of one situation in particular.

Example: Combinatorics and probability

VIDEO 10:51 minutes
Probability of getting a set of cards

Example: Lottery probability

VIDEO 5:10 minutes
What is the probability of winning a 4-number lottery?

Mega millions jackpot probability

VIDEO 5:30 minutes
Probability of winning the Mega Millions jackpot

Generalizing with binomial coefficients (bit advanced)

VIDEO 11:40 minutes
Conceptual understanding of where the formula for binomial coefficients come from

Conditional probability and combinations

VIDEO 16:52 minutes
Probability that I picked a fair coin given that I flipped 4 out of 6 heads.

Conditional probability warmup

VIDEO 5:06 minutes
Conditional probability visualized using trees.

Birthday probability problem

VIDEO 13:16 minutes
The probability that at least 2 people in a room of 30 share the same birthday.

Probability with permutations and combinations

PRACTICE PROBLEMS
Probability questions using permutations and combinations of objects