Author note — to cover

Multiply the branch probabilities along one complete route for that outcome's probability, fraction and decimal answers; two-stage trees, with three stages leaning Higher. Single routes only: combining routes is adding-across-paths. Flag that unchanged second-stage branches assume independence, taught on the Combined events topic. Both tiers. (P8)

Introduction

—coming soon—

Practice and continue

Practice

Multiplying along the branches

The probability of a complete route as the product of its branch probabilities.

Next lesson

Adding across the paths

Finding every path that satisfies the event, then adding their probabilities.