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### #1

Posted 09 August 2008 - 12:03 AM

Dr P: I don’t know the two numbers.

Dr S: I don’t know them either.

Dr P: I still don’t know the two numbers.

Dr S: Neither do I.

Dr P: Now I know the two numbers.

Dr S So do I.

Dr N And so do I.

What are the two numbers?

### #2

Posted 09 August 2008 - 01:33 AM

### #3

Posted 09 August 2008 - 04:05 AM

### #4

Posted 09 August 2008 - 04:15 AM

Are the numbers necessarily different?Three mathematicians—Dr P, Dr S and Dr N—were told that two two digit positive whole numbers had been selected. Dr P was given the product of the two numbers, Dr S was given their sum and Dr N was given neither. The following exchange occurred:

Dr P: I don’t know the two numbers.

Dr S: I don’t know them either.

Dr P: I still don’t know the two numbers.

Dr S: Neither do I.

Dr P: Now I know the two numbers.

Dr S So do I.

Dr N And so do I.

What are the two numbers?

Are you sure they're both two-digit numbers?

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

- Bertrand Russell

### #5

Posted 09 August 2008 - 10:42 AM

This one is quite hard.. Im working on it at the moment.Are the numbers necessarily different?

Are you sure they're both two-digit numbers?

Im taking the viewpoint, that i am Dr N ( who knows nothing about the numbers) I Hope that is right.

### #6

Posted 09 August 2008 - 04:27 PM

This one is quite hard.. Im working on it at the moment.

Im taking the viewpoint, that i am Dr N ( who knows nothing about the numbers) I Hope that is right.

Have worked out the solution

Ill give away a clue

### #7

Posted 09 August 2008 - 08:04 PM

Have worked out the solution

Ill give away a clueSpoiler for Clue

**Edited by Nothanks, 09 August 2008 - 08:08 PM.**

### #8

Posted 09 August 2008 - 10:46 PM

Congrads on your answer, it is what I got!Spoiler for answer

### #9

Posted 10 August 2008 - 12:52 AM

Are the numbers necessarily different?

Are you sure they're both two-digit numbers?

The puzzle was given to me by a friend; he had worked it but gave no info on the numbers having to be different. He did say that the number range is from 10 to 99 which would only include two digit numbers.

### #10

Posted 10 August 2008 - 12:58 AM

The puzzle was given to me by a friend; he had worked it but gave no info on the numbers having to be different. He did say that the number range is from 10 to 99 which would only include two digit numbers.

I worked it out with doubles allowed and the answer comes out fine

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