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Well, between my family and my missus', it's a good year for birthdays this year.
Bear in mind we only have average(ish) size families - we both have 3 sisters and no brothers, what's the odds on these birthdays all being in the same year:

My missus' older sister is 40 this year
My missus' middle sister's hubby is 50 this year
My missus' older sister's hubby is 60 this year
My dad is 70 this year
My missus' grandma is 80 this year

We've been trying to trace our 17th times removed cousins etc, to see if we can add anymore, but to no avail

I wonder what the odds on these birthdays all falling in the same year in 2 average(ish) size families would be (no, I don't really expect anyone to work it out, it's more of a rhetorical question :twisted: ).

LOL, thats really pretty odd, and yet neat.

I wish them all great birthdays.

Wow its gunna be an expensive year!

well, I'm doing a maths degree and in my expert mathematical role I'm going to say that the odds are..... slim.

odds are a crazy thing anyway. try explaining to someone why the odds of you winning the lottery are about 14million to 1, and that the odds of the same set of 6 numbers coming up twice in a row is also about 14million to 1. the madness!

edit: for some reason i also know that when you're playing pool if you just randomly throw all the balls into the triangle there's about a 14,000 to 1 chance they'll form a legal setup. how bored were we that day!?

Lawrence wrote:well, I'm doing a maths degree and in my expert mathematical role I'm going to say that the odds are..... slim.

odds are a crazy thing anyway. try explaining to someone why the odds of you winning the lottery are about 14million to 1, and that the odds of the same set of 6 numbers coming up twice in a row is also about 14million to 1. the madness!

edit: for some reason i also know that when you're playing pool if you just randomly throw all the balls into the triangle there's about a 14,000 to 1 chance they'll form a legal setup. how bored were we that day!?

Ever read Pi? Sounds right up your alley.

(sorry for the slight off topic.)

Lawrence wrote:edit: for some reason i also know that when you're playing pool if you just randomly throw all the balls into the triangle there's about a 14,000 to 1 chance they'll form a legal setup. how bored were we that day!?

Hmm my maths only goes up to A level standard and that was a long time ago lol .
I work it out to 1 in 51 480, so if anyone can show the working-out of this - I would appreciate it .

moonbeam wrote:

Lawrence wrote:edit: for some reason i also know that when you're playing pool if you just randomly throw all the balls into the triangle there's about a 14,000 to 1 chance they'll form a legal setup. how bored were we that day!?

Hmm my maths only goes up to A level standard and that was a long time ago lol .
I work it out to 1 in 51 480, so if anyone can show the working-out of this - I would appreciate it .

I also get that answer, and as a mathematician and keen pool player I'm interested in where the 14000 comes from.

The number 51,480 comes from no. of permuatations possible with 15 balls = 15!. No. of possible legal racks = 7! x 7! - for the different allowed permutations of the distinguishable reds and yellows within the allowed configuration, and of course there is only one place for the black. If you are more leniant with what you define 'legal' you can replace the red at the top with a yellow, and you can reverse the balls in the second row, (although these aren't strictly legal - it should be RYR going from top down, left to right). Dividing by 4 allowing for these permutations yields a probability of 12870 to 1, which is a little closer to 14000! (that's exclamation not factorial!). hmm. I feel like a geek.... back to revision

The odds of everyone of those people having a birthday this year: 100%

Here's one for you:

In any room of 50 people, chances are that two of them will have a birthday on the same day.

Odd, but true.

Mike.

Im so glad I dont celebrate Birthdays.. well, I dont celebrate anyone's except my own and my wifes, and Im all up for getting pi**ed on anyone elses.. presents are a no go.. my wife exclusively

spoken like a true Yorkshire Man I.D

Math Bah..... I got one of them degrees and can't remember the foggiest, it was only 3 years ago

Michael Jay wrote:The odds of everyone of those people having a birthday this year: 100%

Here's one for you:

In any room of 50 people, chances are that two of them will have a birthday on the same day.

Odd, but true.

Mike.

Love that age old problem - really is quite amazing. Even more amazing since it is also true for a group of 23 people. The chances of a group of 'n' people not having a shared birthday between them is given by:

364!/[365^(n-1) . (365-n)!]

Put in n=23 and you get roughly 0.49. Amazing.

A friend of mine used to work as a children's entertainer and cites the first bitter experience which taught him a valuable lesson. He was appearing at a 7 year old's birthday party, doing very well indeed with all the kids hanging on to his every word. Then came prezzie time when he was going to hand over Mom and Dad's big present to the birthday boy and my friend made the mistake of saying, 'It's time for presents, now who has a Birthday?' Of course all the kids put their hands up and expected a present because, as one bright youngster explained, 'We've ALL got Birthdays, but there's only one today'. Luckily additional consolation presents were found otherwise there would have been a riot!

In a 12 month period, my family have had and are going to have:

50th (uncle)
40th (auntie)
80th (grandad, rest his soul)
70th (other grandad)
18th (Me!!! 11 days to go...)

25th anniversay


Quite a year!!!

8 of my family members are born within 5 days either side of Xmas.

Good job I dont celebrate that either!!

Me, my sister, my cousin Joe, and his sister Nicole all have birthdays in the months July and August.