# Mathematical Probability Puzzle

L

#### lindseyc

or could it be 100% boy because tuesday is everything suggests that the difference between the 2 boys is that they were born on seperate days?

#### Steve Prevette

##### Deming Disciple
Staff member
Super Moderator
I'm going with 50%, and getting back to work.

#### Jim Wynne

Staff member
or could it be 100% boy because tuesday is everything suggests that the difference between the 2 boys is that they were born on seperate days?
We have to be able to assume that all of the information needed to solve the problem is included in the question.

#### Ninja

##### Looking for Reality
Trusted Information Resource
I was stuck between 14/28 and 13/27 but I'm convinced it's 13/27 now.
Yep...13/27. Nice call.

#### Wes Bucey

##### Quite Involved in Discussions
As a former Moderator, my first instinct was to look at the posts of the OP who made 18 posts, all in the same month, and then got put "on holiday" (something we used to do to give a "time out" to a burgeoning internet troll.)

My guess is this OP is/was gaming with the sensibilities of all the subsequent posters who tried to reason out a bogus puzzle.

Anyone try to google this riddle to see if the internet has a determination of

OR
• bogus and akin to spam?

#### Ninja

##### Looking for Reality
Trusted Information Resource
Yes. It is (per the internet) a valid puzzle in "mathamagics"

from one site:
Gary Foshee, a collector and designer of puzzles from Issaquah near Seattle walked to the lectern to present his talk. It consisted of the following three sentences: ?I have two children. One is a boy born on a Tuesday. What is the probability I have two boys??
The event was the Gathering for Gardner ....

The math doesn't make sense to me, but it seems like a common enough puzzle FWIW

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