Hi to you all from the UK (Anglesey, Nth Wales)
My friend Cathi and her daughter Manon were born on the same date and also the same time (Feb 12th:-0:55)
Could one of you kind people tell me how to calculate the odds of this happening please
Many thanks
Martin

Wow, same day? I'd say the probability is 1/365=0.0027.

The probability gets even smaller if you consider the time of day....

If you use hour and minutes as a level of precision, then there are 525,600 minutes in a year, so the probability is

1/525600 = 0.000001903

Hi to you all from the UK (Anglesey, Nth Wales)
My friend Cathi and her daughter Manon were born on the same date and also the same time (Feb 12th:-0:55)
Could one of you kind people tell me how to calculate the odds of this happening please
Many thanks
Martin

thats pretty amazing:wave:

Wow, same day? I'd say the probability is 1/365=0.0027.

Not exactly. Because they do not have a unique and independent chance of having the same birth date and time once each year.

The event has only happened once, and is only capable of happening once in all of history. So the true probability is not able to be found.

It would be

1/ (total amount of time that time has, does and will ever exist)

Which is obviously not knowable.

On the other hand, if one only wants to know what the probability is that they share the same month and day, then you are correct.

I think the probability may be somewhat different than that given by quark and JohnM since birthdays may not be evenly spread around the calendar and about the day. That is, birthdays may be more(or less) likely in February and more(or less) likely around 1:00am.

~Matt