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"Cheryl's Birthday" puzzle...
Apr. 19th, 2015 08:33 amI saw there was a viral logic puzzle put out, this girl tells two boys about her birthday - the first gets only the month, and the second gets only the day.
This can be solved but it's a puzzle that bugs me a bit because it's a puzzle based upon that it's a puzzle with a solution. You need to rely on the sufficiency of information to solve it.
That doesn't bother me too much - there are a lot of problems that can be solved by comparing them to another similar problem, recognizing that you can find that they're not just similar, they match - once you figure out how.
For example, a great many puzzles fall into the "pigeonhole principal" - if there are n+1 pigeons and n pigeonholes, at least one hole must have been the entry for more than one pigeon. (And if there are 5n+1 pigeons, one hole must have been the entry for 6 pigeons - or more!)
Anyway: this one's cute, so I figured I'd post a solution behind a cut:
( solution/spoilers follow )
This can be solved but it's a puzzle that bugs me a bit because it's a puzzle based upon that it's a puzzle with a solution. You need to rely on the sufficiency of information to solve it.
That doesn't bother me too much - there are a lot of problems that can be solved by comparing them to another similar problem, recognizing that you can find that they're not just similar, they match - once you figure out how.
For example, a great many puzzles fall into the "pigeonhole principal" - if there are n+1 pigeons and n pigeonholes, at least one hole must have been the entry for more than one pigeon. (And if there are 5n+1 pigeons, one hole must have been the entry for 6 pigeons - or more!)
Anyway: this one's cute, so I figured I'd post a solution behind a cut:
( solution/spoilers follow )
