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The Birthday Paradox Explained

This animation shows why just 23 people give roughly a 50% chance that two share a birthday. It visualizes the surprising jump by counting pairs of people rather than people themselves, showing how comparisons grow much faster than group size. Bars and a running probability curve build up person by person, revealing the tipping point near 23. Useful for students and teachers exploring probability, combinatorics, and why intuition about chance often misleads us.

Narrated · 9:16 · every frame verified for overlaps, spacing and edges before rendering

The prompt that made it

Explain why 23 people are enough for a roughly 50% chance of sharing a birthday. Audience knows basic maths but isn't technical. Make it surprising and visually intuitive.

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