1) Albert knows Bernard cannot know the answer immediately. As 18 and 19 are days that only appear once, the month must not contain those dates, so May and June are eliminated.
2)Bernard is able to identify the month based on knowing it can't be june or may and based on his date. Therefore Bernard cannot have had the number 14. He must have 15,16, or 17.
3) Knowing it is 15, 16, or 17 uniquely identifies the date for albert. Since august has 2 options left, it must be july, and the only date available is July 16.
This is a tricky problem, but it is one that is fairly straightforward to approach step by step. Definitely appropriate for advanced students at age 15. The problem reminds me of the question about how many people on an island have blue/brown eyes.
I haven't done logic problems in a long time, so I may have erred and would welcome alternative interpretations.
I am not sure that is true. If albert knows bernard doesn't know the day at the beginning, it can't be june since the number 18 would be uniquely identifiable as june 18 for bernard from the beginning.
The biggest concern for me actually is that in making this move, amazon is putting itself in direct competition with libraries' ebook/audiobook lending services. Many of those even use the kindle network!
Will amazon continue to allow books to reach those services as soon after release? Do they have the power to stop it in the first place? I think it will be interesting to see how the company, which it is clear has a lot of leverage in the book publishing community, handles competing with a free alternative.
1) Albert knows Bernard cannot know the answer immediately. As 18 and 19 are days that only appear once, the month must not contain those dates, so May and June are eliminated.
2)Bernard is able to identify the month based on knowing it can't be june or may and based on his date. Therefore Bernard cannot have had the number 14. He must have 15,16, or 17.
3) Knowing it is 15, 16, or 17 uniquely identifies the date for albert. Since august has 2 options left, it must be july, and the only date available is July 16.
This is a tricky problem, but it is one that is fairly straightforward to approach step by step. Definitely appropriate for advanced students at age 15. The problem reminds me of the question about how many people on an island have blue/brown eyes.
I haven't done logic problems in a long time, so I may have erred and would welcome alternative interpretations.