4:15 Sample Space Diagrams - Corbettmaths
Corbettmaths clearly shows how to build a sample space diagram and read probabilities from it.
Calculate probability using the sample space
Use the sample space to work out probabilities
5 hand-picked video lessons for this topic, each checked for relevance and clarity, graded by difficulty and labelled by depth. Press play to watch — nothing loads from YouTube until you do.
Sort
Level
Length
Origin
5 shown 4:15 
2:26 Key Skill - Determine a probability from a given sample space.
Dr Frost works one focused example of finding a probability straight from a given sample space.
3:09 Sample Spaces | Statistics & Probability | Maths | FuseSchool
FuseSchool animates how a sample space lists every outcome so you can count probabilities.
7:50 Probability, Sample Spaces, and the Complement Rule (6.1)
Builds sample space diagrams then uses them to calculate probabilities, with a practice question.
16:59 Introduction to Probability, Basic Overview - Sample Space, & Tree Diagrams
A polished, thorough introduction covering sample spaces and calculating basic probabilities.