Year 7 · Geometric Reasoning

Tree
Events

Join your teacher's live session.

Your Name Session Code

Your teacher will give you the session code.

✓ Session Ready

Class

Share this code with your students

—

Students open this app, tap "I'm a Student", enter their name, and type this code.

—

Class Live · 0 students online

PUSH TO

Firebase Configuration

A default database is already configured. You only need to change this if you want to use your own Firebase project. Leave blank and save to restore the default.

Database URL

Default: triangles-3cda9-default-rtdb.firebaseio.com

Year 10 · Probability

Tree Events

This drill is about reading the question. When you see P(same colour) or P(at least one blue) or P(both red), which branches of the tree are you actually being asked about?

You'll see a tree diagram and a probability description. Click every branch (leaf) that matches the description, then hit Check. The tool will tell you which ones you got right and which ones you missed.

The phrases you'll meet

P(both red) / P(all red) — every draw is red. Just one branch.
P(same colour) — every draw matches. Two or three branches depending on how many colours are in play.
P(different colours) — at least one draw differs from another.
P(at least one blue) — one or more blues. Includes "all blue" and "exactly one blue" both.
P(no blue) — zero blues. Often easier to spot than "at least one".
P(exactly one blue) — exactly one — not zero, not two.
P(red then blue) — order matters. Only the specific path.

Three tree shapes

The drill walks through trees with increasing complexity:

Two draws, two colours (4 leaves) — the warm-up
Two draws, three colours (9 leaves) — vocabulary expands
Three draws, two colours (8 leaves) — "exactly two" makes sense here

This is a comprehension drill, not a calculation drill. You don't compute the probability — you identify which branches the description is asking about. Once you can do that confidently, the calculation is just adding up the leaf probabilities.

Tree Events · Probability · 17 questions, click branches to identify

Complete

Tree Events Mastered

★

You've practised translating probability descriptions into branches on a tree diagram. The vocabulary is now in your hands.

Quick reference — what each phrase usually means:
• "Both/All [X]" — every draw is X. One branch (or one path).
• "Same colour" — every draw matches. One branch per colour.
• "Different colours" — branches where at least one draw differs.
• "At least one [X]" — one or more X's. Often easier as 1 − P(no X).
• "No [X]" — zero X's. Branches that avoid X entirely.
• "Exactly one [X]" — only one X. Not zero, not two.
• "[X] then [Y]" — order matters. One specific path.

Working-out whiteboard

Scientific calculator

Class

Firebase Configuration

Tree Events

The phrases you'll meet

Three tree shapes

Tree Events Mastered

Import Student Data

Working-out whiteboard ⤢ Expand ✕

Scientific calculator ✕

TreeEvents

Class

Firebase Configuration

Tree Events

The phrases you'll meet

Three tree shapes

Tree Events Mastered

Import Student Data

Working-out whiteboard

Scientific calculator

Tree
Events