To see the problem you will need to play the video. But you will then need to pause the video before it runs into the answer.
I found it fairly easy, but it seems to be stumping people.
There is no clever or difficult maths involved, only logical thinking.
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>> To see the problem you will need to play the video.
Can you tell us where it is then?
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s'embarrassing.
www.bbc.com/news/world-asia-32297367
Last edited by: No FM2R on Tue 14 Apr 15 at 14:01
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goo.gl/gIHrlY (Guardian)
That one?
Easy with a pen to cross off the ones eliminated by the statements.
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Sorry, crossed.
A bit like doing sudoku. Sums not required.
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>>A bit like doing sudoku
Killer Sudoku from the Times, the only way to go.
I used to love the ordinary Sudoku, but I find the Killer ones much more entertaining.
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I read it through a couple of times and don't have a scooby. Although if it sudoku related no surprise, I've never manged to do one in my life. Same goes for crosswords, I guess my brain isn't wired up that way.
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Watched the video with maths bloke explaining it, still don't really get it.
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I don't know if I can explain this clearly....
May 15 16 19
June 17 18
July 14 16
August 14 15 17
Both boys know all the possible dates (month & day)
Albert knows which Month it is
Bernard knows which day it is
Albert (Month) says he knows that Bernard (Day) doesn't know the date (day & month).
If Bernard (Day) had 19, then Bernard (Day) would know it was May 19 (the only 19).
If Bernard (Day) had 18, then Bernard (Day) would know it was June 18 (the only 18).
Therefore Albert (Month) *knows* that Bernard (Day) doesn't have 19 or 18. Therefore Albert (Month) *knew* the month was neither May nor June as he has July or August.
So we're down to....
July 14 16
August 14 15 17
Bernard (Day) says he now knows the date (Day & month). If Bernard (Day) had 14, then it could be July or August. So Bernard (Day) does not have 14. Since the other three dates (15, 16 and 17) are unique, then Bernard (Day) does indeed know the date (Day and Month).
So we're down to.....
July 16
August 15 17
Albert (Month) says he now knows. Since Albert (Month) only knows month, then if Albert (Month) had August he wouldn't know 15 or 17. So Albert (Month) must have July, then there is only 16.
I do hope I didn't screw that up.
Last edited by: No FM2R on Tue 14 Apr 15 at 15:07
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>> I do hope I didn't screw that up.
>>
>>
Nope, well done Mark,
now if we can just get you to call it a maths problem rather than that awful American word math
....
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It's a mathematical problem, abbreviated to math problem. an "s" is illogical and unnecessary
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I think it depends on whether "math" is being used as an abreviation of "mathematics" or "mathmatical"
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>> I think it depends on whether "math" is being used as an abreviation of "mathematics"
>> or "mathmatical"
>>
When you say "math problem" you are presumably using the adjective "mathematical as you would have otherwise presumably used the phrase a "problem in mathematics".
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>> an "s" is illogical and unnecessary
>>
Physic, logistic, statistic, static, dynamic, classic, kinetic, ?
And of course big game hunting - shot a lot of elephant, gazelle, lion, etc. :)
Last edited by: Cliff Pope on Tue 14 Apr 15 at 18:00
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Thanks for trying, but I don't really get these sort of puzzles. No drama.
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Back in the days when something like an Altair Design Pad was the most exciting thing you could do in a evening, you used to be able to buy little books which were full of those kind of puzzles. They had a little grid so you could tick things, to make it easy - but somehow it never did seem to be that easy.
But they were all variants on the same theme - often whodunnit type things, sometimes "who wore the yellow socks", that kind of thing. I expect that was partly why they fell out of favour.
You can probably still get them in some timewarp place or other. Amazon, probably, or the Amazon if not there.
Last edited by: Crankcase on Tue 14 Apr 15 at 16:10
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>> You can probably still get them in some timewarp place or other. Amazon, probably, or
>> the Amazon if not there.
The first puzzle in this (via the 'Look inside' link) looks like it might be similar:
www.amazon.co.uk/Challenging-Logic-Puzzles-Official-Puzzle/dp/1402705417
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>> The first puzzle in this (via the 'Look inside' link) looks like it might be
>> similar:
>> www.amazon.co.uk/Challenging-Logic-Puzzles-Official-Puzzle/dp/1402705417
>>
Thanks for that. Not quite, although similar.
Of course, that meant I had to Google, and inevitably, with whatever is the opposite of serendipity I mistyped my query. Let's just say my eyes flew open sharply as I was presented with the results of my search for an old pizzle.
Sigh.
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I also must have misunderstood the question because my initial answer was:" they both know because she told them"!
>> Cheryl them tells Albert and Bernard (A + B for short) separately the Month and Day of her birthday respectively.
i.e Cheryl tells both - both the day and month!! the fact that it was July 16 is irreverent.
Last edited by: devonite on Tue 14 Apr 15 at 16:13
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>> I also must have misunderstood the question because my initial answer was:" they both know
>> because she told them"!
>>
>> >> Cheryl them tells Albert and Bernard (A + B for short) separately the Month
>> and Day of her birthday respectively.
>>
The key word is "respectively". That changes the meaning from she told both of them both facts, to she told one one fact the other the other.
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SWMBO came in talking about this so I started to step through your logic Mark. It's all way over my tolerance level but she has a query:
"Therefore Albert (Month) *knows* that Bernard (Day) doesn't have 19 or 18. Therefore Albert (Month) *knew* the month was neither May nor June as he has July or August."
What tells you he has July or August (or doesn't have May or June)?
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Albert (month) KNEW that Bernard (Day) didn't have 18 or 19.
Since Albert has no idea which days Bernard does have, the only way he could KNOW that Bernard didn't have 18 or 19 is if he (Albert) knew that the month was not May or June.
If the month was May or June , then Albert (Month) could not KNOW that Bernard (Day) had neither 18 or 19.
Last edited by: No FM2R on Tue 14 Apr 15 at 19:00
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When I went back down after typing that she'd got it all on her own... But thanks :-)
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I found it fairly easy too.
I can't be bothered with Sudoku. Once you've done one, you've done them all.
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Math problem from Singapore - VxFan
