you sign up for a class at a local college, and you go to your first lecture. You get there first and sit in the middle of the classroom. What are the chances that the person that sits to your right is male? You cannot say 50/50 because of the 2 possible outcomes. If the school has a 90% female population, the chances are only 10%. Suppose the whole school has 4000 students; what are the chances that there is at least one other person in that school that shares your birthday? Please, estimate explaining how you come up with your estimate

Respuesta :

Not counting leap years, the chance that a person doesn't have the same birthday as you is 364/365. Since there are 4000 people in the school, you would multiply this chance 4000 times like this: 
[tex]( \frac{364}{365})^4^0^0^0[/tex]
Since that will give you the chance that nobody has the same birthday as you, you simply subtract that number from 1 (100%).
So the chance that someone has the same birthday as you is 1-.0000171426= .999928, which is roughly 99.9928%