Catchalotto

[ido]

(11-28-2009 01:26 AM)Frank Wrote:  

Quote:"Birthday problem", can you expand on that?

Sure ........what is the minumum number of people in a room before there is a 50% chance of 2 people sharing the same birthday ?

http://mathforum.org/dr.math/faq/faq.birthdayprob.html

Enjoy !

Edit:-

The answer is 23 which is unbelivably small because the more people there are in the room, the more multiple comparisons (person to other person) are taking place.


If instead of comparing birthdays, each had a ticket in their pocket with a number 1 to 365 and they compared those, the problem would be the same, with the same result.

Now expand the ticket to a number between 1 and 13,983,816. How many people need to be in the room until the probability that 2 numbers matched was more than 50% ? Like I said its 4404 (50.01%).

Hi Frank&Catchalotto,

..."what is the minumum number of people in a room before there is a 50% chance of 2 people sharing the same birthday ?...."

surptisingly my automatic mental replay was (only)two twins ever give 100%!!!
The funny thing is that after some time every player by acumulating
his experience starts mentaly seriosly to consider the twins problem in it's two main aspects - everithing may happen &ever is possible something very probable not to happen.