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The birthday coincidence


Best Answer Prime, 15 February 2013 - 08:27 PM

Time's up.

Spoiler for solution

 

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10 replies to this topic

#1 bonanova

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Posted 15 February 2013 - 07:57 AM

I remarked to a friend how surprised I was to learn that as few as 23 randomly chosen people give better than even odds of a shared birthday. She agreed, saying three of her friends shared her birthday. The product of their ages is 2450 cubic years, she said, and their sum, remarkably, is twice your age [meaning mine.] It was a statement, to be sure, but I knew from the twinkle in her eye it was also a challenge.

 

I scribbled on the back of an envelope for a moment. Well? she smiled, got you stumped? In fact I could not answer. I'm afraid I need another clue. OK, she said, I am older than any of the three, and my age is equal to the product of the ages of the two youngest.

 

Triumphantly I announced the ages of her three friends.

 

p.s. That's a challenge. ;)


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The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell

#2 jddouglas

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Posted 15 February 2013 - 04:02 PM

How about this:

 

Spoiler for

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#3 Prime

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Posted 15 February 2013 - 04:13 PM

How about this:

 

Spoiler for

If that was the case, why would bonanova need another clue?


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Past prime, actually.


#4 bhramarraj

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Posted 15 February 2013 - 04:18 PM

Spoiler for my age


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#5 James33

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Posted 15 February 2013 - 04:23 PM

I don't think there are any integer solutions to this.


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#6 Morningstar

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Posted 15 February 2013 - 04:58 PM

Are we using your age as shown on your profile page (72)?


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The cake is a lie.

#7 bonanova

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Posted 15 February 2013 - 05:57 PM

Are we using your age as shown on your profile page (72)?


No, Sherlock, ;) but great investigative reporting!


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The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell

#8 James33

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Posted 15 February 2013 - 06:12 PM

Are we using your age as shown on your profile page (72)?


No, Sherlock, ;) but great investigative reporting!

Oh that makes things different. In that case I think there are several solutions.

 

Spoiler for


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#9 bonanova

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Posted 15 February 2013 - 07:06 PM

 


Are we using your age as shown on your profile page (72)?

No, Sherlock, ;) but great investigative reporting!
Oh that makes things different. In that case I think there are several solutions. 
Spoiler for

 

Your statement is correct.
Your question is valid.
But since you don't yet have a unique answer, it's your question to answer.

Btw, no offense intended by the Sherlock comment
. :)


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The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell

#10 Morningstar

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Posted 15 February 2013 - 08:15 PM

 

 


Are we using your age as shown on your profile page (72)?

No, Sherlock, ;) but great investigative reporting!
Oh that makes things different. In that case I think there are several solutions. 
Spoiler for
Your statement is correct.
Your question is valid.
But since you don't yet have a unique answer, it's your question to answer.

Btw, no offense intended by the Sherlock comment. :)

None taken.


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The cake is a lie.




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