Separate a pattern’s chance in one window from the time you wait for it.
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First lesson in this subject: Count equally likely outcomes
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Heads (H) · Tails (T)
For a fair coin, HH and HT each have probability 1/4 in two tosses. But a search keeps going until a pattern first appears. Its windows overlap, so counting them as independent opportunities gives the wrong answer.
You are reading the opening. Members read every lesson and guide in full. A free account reads the first lesson in each subject in full.
You are reading the opening. Your free account reads the first lesson in each subject in full. Members read every lesson and guide in full.
First lesson in this subject: Count equally likely outcomes
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Practice · Race coin patterns and discover why equally likely sequences can have different waiting times.
Book · Count outcomes, update chances with new information, and compare decisions through worked examples.
Previous lesson · Use the chance of no match to understand why shared birthdays arrive surprisingly soon.
Next lesson · Track both patterns on one sequence and count unfinished races.
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