People's birthdays are taken one at a time at random. How many times can you do this before you find two people with the same birthday?
Months
January
February
March
April
May
June
July
August
September
October
November
December
Generate Birthdays
Birthdays: 0  Matches: 0
Minimum number of people
The minimum number of people for there to be a specific probability of two or more coincident birthdays
Probability:

Probability
The probability of two or more people sharing a birthday
Number of people:
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This question appears in the following syllabi:
Syllabus  Module  Section  Topic  Exam Year 

AQA ALevel (UK  Pre2017)  S1  Probability  Experimental   
AQA AS Maths 2017  Statistics  Probability  Experimental Probabilities   
AQA AS/A2 Maths 2017  Statistics  Probability  Experimental Probabilities   
CBSE XII (India)  Probability  Probability  Repeated independent (Bernoulli) trials and binomial distribution   
CBSE XI (India)  Statistics and Probability  Probability  Random experiments, outcomes, sample spaces (set representation)   
CCEA ALevel (NI)  S1  Probability  Experimental   
CIE ALevel (UK)  S1  Probability  Experimental   
Edexcel ALevel (UK  Pre2017)  S1  Probability  Experimental   
Edexcel AS Maths 2017  Statistics  Probability  Experimental Probabilities   
Edexcel AS/A2 Maths 2017  Statistics  Probability  Experimental Probabilities   
I.B. Higher Level  5  Probability  Experimental   
I.B. Standard Level  5  Probability  Experimental   
Methods (UK)  M15  Probability  Experimental   
I.B. (MSSL)  3  Probability  Experimental   
OCR ALevel (UK  Pre2017)  S1  Probability  Experimental   
OCR AS Maths 2017  Statistics  Probability  Experimental Probabilities   
OCR MEI AS Maths 2017  Statistics  Probability  Experimental Probabilities   
OCRMEI ALevel (UK  Pre2017)  S1  Probability  Experimental   
PreCalculus (US)  E4  Probability  Experimental   
PreU ALevel (UK)  Prob  Probability  Experimental   
Scottish (Highers + Advanced)  HS  Probability  Experimental   
Scottish Highers  S  Probability  Experimental   
Universal (all site questions)  P  Probability  Experimental   
WJEC ALevel (Wales)  S1  Probability  Experimental   