An investigation into chance
Probability Detective
Case briefing
Your mission
How it works
By the end you can
Observed
Solid shapes: what really happened in your trials.
Solid shapes: what really happened in your trials.
Theory
Dashed lines: what the rules predict on average.
Dashed lines: what the rules predict on average.
Case 1 of 3
The Coin Lab
A Watch a demo
Theory
Observed
B Your investigation
2. Predict first
heads out of 100 flips
Your prediction is never marked wrong. The flip buttons appear once you save or skip.
3. Run the experiment
4. Evidence
No flips yet. Choose a coin, predict, then flip.
Observed (solid)Theory (dashed)
Latest run: heads and tails
How the heads proportion changed during the latest run
Compare sample sizes
Each dot is one run with the current coin. The dashed line is the theory.
Streak check
Clue questions
C Fresh case: the mystery coin
No mystery flips yet.
Case 2 of 3
The Dice Investigation
A Demo: 36 outcomes
Choose a sum to highlight its outcomes.
B Your investigation
2. Predict first
3. Roll
4. Evidence
No rolls yet. Predict, then roll.
Observed proportion (solid)Theory (dashed)
Latest run
Clue questions
C Fresh case: count the chances
out of 36 outcomes
Case 3 of 3
The Fair-Game Designer
A Warm-up: two coins
Check with the simulator
B Design a fair game
Points per score
Predict
Play rounds
No rounds played yet.
Observed points per round (solid)Expected (dashed)
C Final challenge: a brand-new game
Collect evidence
out of 36
Detective’s report