From there, people around the world have been trying to figure out Cheryl’s birthday, or at least wondering why she couldn’t just save everyone a lot of trouble and be more direct with Albert and Bernard?
The wording of the problem is terrible, so here is a clearer version, which makes some of the assumptions more obvious but which does not change any of the underlying logic of the problem:
Albert and Bernard just met Cheryl. “When’s your birthday?” Albert asked Cheryl.
Cheryl thought a second and said, “I’m not going to tell you, but I’ll give you some clues.” She wrote down a list of 10 dates:
May 15 — May 16 — May 19
June 17 — June 18
July 14 — July 16
August 14 — August 15 — August 17
“My birthday is one of these,” she said.
Then Cheryl whispered in Albert’s ear the month — and only the month — of her birthday. To Bernard, she whispered the day, and only the day.
“Can you figure it out now?” she asked Albert.
Albert: I don’t know when your birthday is, but I know Bernard doesn’t know, either.
1. "the original wording wasnt terrible btw." In response to Reply # 0
-The Knicks’ coaching search still includes a lone frontrunner, Kurt Rambis, whose qualifications for the position include a strong relationship with Jackson and a willingness to take the job.
-The Knicks’ coaching search still includes a lone frontrunner, Kurt Rambis, whose qualifications for the position include a strong relationship with Jackson and a willingness to take the job.
7. "True, what forte wrote was simpler, i guess that's part of doing word " In response to Reply # 5
problems...provided that it cant be interpreted more than one way. The person that showed it to me couldn't figure it out bc they didn't know what respectively meant.
-The Knicks’ coaching search still includes a lone frontrunner, Kurt Rambis, whose qualifications for the position include a strong relationship with Jackson and a willingness to take the job.
13. "I'll just say how I arrived at my guess" In response to Reply # 0
There are two months that have three days. I assume those would be the most difficult to guess from, from Albert's perspective. There are two months with unique days. So it has to be one of those days in order for Bernard to know. I picked the unique day on the month that had 3 days to choose from.
26. "I think I'm getting there. But I'm ready to give up (spoilers)" In response to Reply # 0
Here is my progress so far:
If Bernie knows for sure that Al doesn't know, we can exclude June 18 and May 19. This is because if she told Al that the date was either 18 or 19, he would be able to answer with certainty.
The fact that Bernie knows for sure that Al doesn't know tells us. that the month is not May or June. If she told Bernie that the month was May or June, then he would not be able to exclude May 19 or June 18.
So I am left with July 14, Aug 14, Aug 15, July 16, Aug 17.
29. "Here is my question, how do you systematically solve problems like this?" In response to Reply # 0
I understand that this was a test on a math exam, but what exactly are they testing for?
How did people approach this problem? Is the approach always process of elimination?
I never like these sort of problems of test of intelligence or aptitude because it seems to me that people who do well on them are able to answer these sort of questions because they've seen similar questions before.
I thought the LSAT was rigged because it had logic games and you could easily make your score jump by taking a class that taught you how to do logic games. Seems unfair to the folks who couldn't afford the class.
********** "Everyone has a plan until you punch them in the face. Then they don't have a plan anymore." (c) Mike Tyson
"One of the most important things in life is what Judge Learned Hand described as 'that ever-gnawing inner doubt as to whether you're
30. "I definitely approached it using process of elimination" In response to Reply # 29
I learned a lot of facts and concepts in college, but the most valuable thing I learned was analytical thinking. If you didn't pick that up in undergrad, your school failed you.
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