View all of Khan Academy’s lessons and practice exercises on probability and statistics here.

Learn statistics and probability—everything you'd want to know about descriptive and inferential statistics.

You've experienced probability when you've flipped a coin, rolled some dice, or looked at a weather forecast. Go deeper with your understanding of probability as you learn about theoretical, …

Probability and combinatorics are the conceptual framework on which the world of statistics is built. Besides this important role, they are fascinating, fun, and often surprising!

Practice Probability with permutations and combinations Get 3 of 4 questions to level up!

This formula is derived from the definition of conditional probability and helps in calculating joint probabilities of dependent events.

We can build a formula for this type of problem, which is called a binomial setting. A binomial probability problem has these features:

If you're curious about the mathematical ins and outs of probability, you've come to the right unit! Here, we'll take a deep dive into the many ways we can calculate the likelihood of different outcomes.

You can prove that if P (A|B) = P (A) then P (B|A) = P (B). (proof is fairly straightforward, just use the definition of conditional probability) So knowing P (A|B) = P (A) is enough to prove independence.

What is P (A) , the probability that the student plays soccer? What is P (B) , the probability that the student plays basketball? What is P (A and B) , the probability that the student plays soccer and …