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Things That Are on Your Mind

My father needs to stop interpreting me saying "Fine. I'll get an iPhone," as "I want an iPhone," and start interpreting it as "Everything is going mobile and I don't really have a choice." He keeps pressuring me to get one. The last time I said something like that, he did some stupid victory dance because he knows I hate the iPhone and and thought he successfully convinced me to worship Apple like he does. I'm tired of it.
 
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Raindrop14

Soldier for Christ!
Joined
Jan 29, 2011
Location
E-Arth
I have to attend a seminar in an hour so I can qualify for Directed Practice next semester. Kinda nervous..

You'llllllllllllllllllllllllllllllllll do AWESOME!!!!!!!!! =) No worries, get all that nervous energy out by jumping around or something, and knock their socks off!

Oops I'm back to fretting now. Man I hate my brain sometimes.

Ah, yes, the happy-now-no-wait-I'm-worried-oh-now-I'm-happy days. Keep on trekin' cuz ya rock.

My father needs to stop interpreting me saying "Fine. I'll get an iPhone," as "I want an iPhone," and start interpreting it as "Everything is going mobile and I don't really have a choice." He keeps pressuring me to get one. The last time I said something like that, he did some stupid victory dance because he knows I hate the iPhone and and thought he successfully convinced me to worship Apple like he does. I'm tired of it.

I'm sorry. I have the polar opposite parents, they hate Apple and will never let me get any of their products as long as I live under their roof. Not that I care for Apple anyway. =P Just keep going against the Apple, yo, you wont have to live with people nagging you about it forever!
 

misskitten

Hello Sweetie!
Joined
Jun 18, 2011
Location
Norway
I think I might have gotten the answer...

Albert: I don't know when Cheryl's birthday is [...]
Now we know that Albert only knows the month of Cheryl's birthday. If we look at all the different options, each month has more than one option. May has 3 options (May 15, May 16, May 19), June has 2 options (June 17, June 18) and so on. This is why Albert does not know. No matter what month he got, he doesn't have a definite answer because there are more than one choices.

Albert: [...] but I know that Bernard does not know."
We know that Bernard only has the date. So here are the possible dates he got, and the months which they belong to:
14 (Jul, Aug)
15 (May, Aug)
16 May, Jul)
17 (Jun, Aug)
18 (Jun)
19 (May)
Both 18 and 19 have only one possible option. Meaning if he got 18 or 19, he would get his answer.
But Albert knows that Bernard doesn't know. Meaning he knows that Bernard's date isn't 18 or 19. The only way Albert can be sure of this is if the month he got isn't May or June. That means Cheryl's birthday is either in July, or August.

Bernard: At first I don't know when Cheryl's birthday is, but I know now.
Bernard follows Albert's thought process and knows that Cheryl's birthday is either in July or August. That means the dates which Bernard are one of the following:
14 (Jul, Aug)
15 (Aug)
16 (Jul)
17 (Aug)
We know that Bernard got his answer. Since he only has the date, not the month, his date can't be 14. Because the month could be July or August. That means that Bernard's date is 15, 16, or 17.

Albert: Then I also know when Cheryl's birthday is.
Albert follows Bernard's thought process and comes to an answer. His month either is July or August. And since we ruled out 14 from above, here are the options:
July (16)
August (15, 17)
Since Albert has come to a conclusion, we know that the month he got must be July as it only has one option.

Therefore, Cheryl's birthday is July 16.

Wow, that was a waste of half an hour :3
^ My hand at the problem

I actually disagree:
See, the problem doesn't specify that Albert got month and that Bernard got the date, and it makes no sense that the person who got the month is the first one to speak since the person who got the month will not know (also if one person is given the month, he doesn't automatically know that the other person wasn't given a unique date, he wouldn't know that until the other person had spoken).

However if Albert got the date and says "I don't know" then he gives Bernard a chance to eliminate.

Albert specifies that the date he's been given is not one that only happens in one month, so May 19 and June 18 are eliminated.

What's left:
May (15, 16)
June (17)
July (14, 16)
August (14, 15, 17)

Bernard says that with Albert saying this, he now knows which day it is. And if Bernard was only given the month, this can only be June, because if it had been any other month, Bernard still wouldn't know which date Albert have, because there would still be more options.

Albert says that when Bernard says he knows, that means he knows too, which means that Bernard gave him a clue.

Now if Albert's date had been 14, 15 or 16, he would not get any more information from Bernard because each of the possible months for those dates have more than one option and he'd been none the wiser, but Albert now knows, which means his date could only have been 17, and by Bernard confirming he knows, it means Bernard had to have had the month of June, since that is the only option that can be singled out in this stage of the elimination process.
 

Eduarda

Srishti is annie is eduarda right?
Joined
May 28, 2010
Location
Ontario, Canada.
Oh my gosh misskitten disagreed with my solution. Quick. I have to hide myself. :goodness:

I actually disagree:
See, the problem doesn't specify that Albert got month and that Bernard got the date, and it makes no sense that the person who got the month is the first one to speak since the person who got the month will not know (also if one person is given the month, he doesn't automatically know that the other person wasn't given a unique date, he wouldn't know that until the other person had spoken).

However if Albert got the date and says "I don't know" then he gives Bernard a chance to eliminate.

Albert specifies that the date he's been given is not one that only happens in one month, so May 19 and June 18 are eliminated.

What's left:
May (15, 16)
June (17)
July (14, 16)
August (14, 15, 17)

Bernard says that with Albert saying this, he now knows which day it is. And if Bernard was only given the month, this can only be June, because if it had been any other month, Bernard still wouldn't know which date Albert have, because there would still be more options.

Albert says that when Bernard says he knows, that means he knows too, which means that Bernard gave him a clue.

Now if Albert's date had been 14, 15 or 16, he would not get any more information from Bernard because each of the possible months for those dates have more than one option and he'd been none the wiser, but Albert now knows, which means his date could only have been 17, and by Bernard confirming he knows, it means Bernard had to have had the month of June, since that is the only option that can be singled out in this stage of the elimination process.

That is a good possibility. But the question said "Cheryl then tells Albert and Bernard separately the month and the day of her birthday respectively." Now, respectively means in order in what was said before. So since month was mentioned before date, and Albert was mentioned before Bernard, Albert got the month, and Bernard got the date :) Unless I've been using the word respectively wrong my whole life, of course, which sadly wouldn't surprise me
ASv0hbs.gif
 

misskitten

Hello Sweetie!
Joined
Jun 18, 2011
Location
Norway
Oh my gosh misskitten disagreed with my solution. Quick. I have to hide myself. :goodness:



That is a good possibility. But the question said "Cheryl then tells Albert and Bernard separately the month and the day of her birthday respectively." Now, respectively means in order in what was said before. So since month was mentioned before date, and Albert was mentioned before Bernard, Albert got the month, and Bernard got the date :) Unless I've been using the word respectively wrong my whole life, of course, which sadly wouldn't surprise me
ASv0hbs.gif

True, but how can Albert know that Bernard doesn't know if he was given the month and he's the first to speak?
 

Eduarda

Srishti is annie is eduarda right?
Joined
May 28, 2010
Location
Ontario, Canada.
True, but how can Albert know that Bernard doesn't know if he was given the month and he's the first to speak?
That is because from my solution, the month Albert received is July. So Albert knows that the day which Bernard got is either 14 or 16 as both dates fall under July. But at the same time, both dates also fall under August (14) and May (16). So if Bernard has 14, he wouldn't know if it's in August or July. And if Bernard has 16 he wouldn't know if it's in May or July. So Albert can assume that Bernard doesn't know the answer.
 

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