# Birthday Paradox

This going to be a tough one!!

While surfing through the net I came across a very interesting concept- Birthday Paradox

I tried to pose the interesting paradox in question form, so that you can use your grey cells.

After some discussion on these questions we will look into the concept of Birthday Paradox deeply.

Q 1. “what’s the probability that, in a set of randomly chosen 23 people, will any given pair share the same birthday?”

Q 2. “what’s the probability that, in a set of randomly chosen 57 people, will any given pair share the same birthday?”

Q 3. “when is the probability 100%, that in a set of randomly chosen people, atleast one given pair share the same birthday”

If this is not your cup of tea, try the easier one’s on the site

4 Comments

please email all the above question’s answers @ my email…I willl be grateful 2 u…

1. (1/365)^22 as, 365*1^22 / 365^23

2. (1/365)^56 as, 365*1^56 / 365^57

3. when there are atleast 366 people

@ Mohit: This is wrong, but we will rectify it later.

BTW, there are 365 possible birthdays (if we ignore leap years) and not 7

Let others also try.

1. (1/7)^23

2. (1/7)^57

3. when there are atleast 8 people

pls rectify if incorrect