Probability of birthdays on every day

  • Thread starter duzza275
  • Start date
  • #1
2
0

Main Question or Discussion Point

Please may someone help me with this and if you have an answer please may you show all the steps that you took. This is not a prep question but I was thinking about it and wondering what the answer was but my statistics skills are not good enough for this yet. :)

If I have a randomly selected group of 430 people. What is the probability that there is 1 birthday on ever single day in the year? (Assume that it is a 365 day year)

Thanks
 

Answers and Replies

  • #2
1,065
53
Good luck...I guess you are asking for an answer from the purely mathematical point of view assuming a uniform distribution of births throughout the year?

I am wondering because that's not what REALLY happens. Weather and holidays affect love-making; last I heard, new year's is a 'lucky' day and so, we have a lot of September people.

Just look at the animal kingdom; ok, they don't have holidays, but look at how the times when, basically, the entire group gives birth within a matter of days or weeks ruled by migratory patterns, availability of food, weather conditions, etc.

Anyway, just a thought.
 
  • #3
2
0
Yeh I am looking for an answer with a mathematical point of view that assumes that births are evenly distributed throughout the year.
 
  • #4
329
0
Please may someone help me with this and if you have an answer please may you show all the steps that you took. This is not a prep question but I was thinking about it and wondering what the answer was but my statistics skills are not good enough for this yet. :)

If I have a randomly selected group of 430 people. What is the probability that there is 1 birthday on ever single day in the year? (Assume that it is a 365 day year)

Thanks
This is the "Coupon Collector's Problem". See my reply to this post

https://www.physicsforums.com/showthread.php?t=523620

for a formula for the probability.
 

Related Threads on Probability of birthdays on every day

  • Last Post
Replies
2
Views
1K
  • Last Post
Replies
2
Views
3K
  • Last Post
Replies
5
Views
4K
  • Last Post
Replies
14
Views
2K
  • Last Post
Replies
4
Views
2K
  • Last Post
Replies
7
Views
1K
Replies
2
Views
830
  • Last Post
Replies
4
Views
2K
  • Last Post
Replies
6
Views
1K
Replies
12
Views
11K
Top