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Session 3: Experimental vs. Theoretical Probability

Why does flipping a coin 10 times not always give 5 heads? Learn the difference between what should happen and what does happen.

4 Lessons
~2 hours total
6 Practice Activities
Session Quiz

Your Progress

Lessons 1-4
Practice
Session Quiz
Review

Learning Objectives

By the end of this session, you will be able to:

  • Distinguish between theoretical and experimental probability
  • Conduct probability experiments and record results
  • Understand the law of large numbers
  • Explain why small samples produce unreliable results

Why This Matters

Theory tells you what should happen. Experiments show what actually happens. Understanding the gap between them is one of the most important ideas in all of data science.

Session Lessons

1

What Should Happen: Theoretical Probability

Calculate what should happen based on math alone — before running any experiment.

~30 minutes Discussion

2

What Actually Happens: Experimental Probability

Run experiments and see how results compare to theoretical predictions.

~30 minutes Activity

3

The Law of Large Numbers

The more you repeat an experiment, the closer results get to the theoretical prediction. This is one of the most powerful ideas in probability.

~30 minutes Activity

4

Why Small Samples Fool Us

Small groups of data can show dramatic patterns that disappear with more data. Learn why this matters for real-world decisions.

~30 minutes Discussion

After the Lessons

Practice Activities

6 hands-on activities at easy, medium, and challenge levels.

Practice Activities

Session Quiz

8 questions to check your understanding. Get 6+ right to pass!

Take Session Quiz

Study Materials

Study guide and family guide for review.

Begin Session 3 →