Probability Province

Levels 49–99 · probability

A land of chance and likelihood. Calculate outcomes, events, and expected values to tip the odds in your favor.

Study Before You Play

Brush up on these topics to sharpen your skills for this zone.

Probability Basics

Learn what probability is, how to express it as a fraction, and how to find the probability of simple events.

Compound Probability

Calculate probabilities of two or more events occurring together or in sequence.

Probability: And / Or

Learn union and intersection rules — adding and multiplying probabilities for compound events.

Conditional Probability

Understand how prior knowledge changes the probability of an event using P(A|B).