9 logic puzzles that only real intellectuals can handle
1. Cheryl’s birthday
Suppose some Bernard and Albert recently met a girl Cheryl. They want to know when her birthday is so they can prepare gifts. But Cheryl is something else. Instead of answering, she hands the guys a list of 10 possible dates:
|May 15||16th of May||May 19|
|June 17||June 18|
|the 14 th of July||July 16|
|August 14||August 15||August 17|
Predictably finding the boys unable to figure out the correct date, Cheryl whispers into Albert’s ear only the month of her birth. And Bernard – also quietly – only a number.
“Hmm,” says Albert. I don’t know when Cheryl’s birthday is. But I know for a fact that Bernard doesn’t know that either.
“Ha,” says Bernard. “At first I didn’t know when Cheryl’s birthday was either, but now I know it!
“Yeah,” Albert agrees. “Now I know too.
And they call the correct date in unison. When is Cheryl’s birthday?
If you can’t find the answer right away, don’t be discouraged. For the first time this question was raised at the teenage mathematical Olympiad in Singapore, which is famous for the highest educational standards. After one of the local TV presenters posted a screenshot of this puzzle on Facebook*, it became viral: tens of thousands of Facebook*, Twitter, Reddit users tried to solve it. But not everyone succeeded.
We are confident that you will succeed. Do not reveal the answer until you have at least tried it.
2. How old are the daughters
Two former classmates once met on the street, and such a dialogue took place between them.
– How are you?
– Okay. Two daughters are growing up, still preschoolers.
— And how old are they?
– Well, uh … The product of their ages is equal to the number of pigeons under our feet.
This information is not enough for me!
The older one looks like her mother.
Now I know the answer to my question!
So how old are the daughters of one of the interlocutors?
3. Where is my car?!
They say this task is given to elementary school students in Hong Kong schools. Children solve it literally in a matter of seconds.
What is the number of the parking space that the car occupies.
4. Love in Kleptopia
Jan and Maria fell in love with each other, communicating only via the Internet. Ian wants to mail Maria’s engagement ring to propose. But here’s the problem: the lovers live in the country of Kleptopia, where any package sent by mail will certainly be stolen – unless it is enclosed in a box with a lock.
Jan and Maria have a lot of locks, but they cannot send the keys to each other – after all, the keys will also be stolen. How can Ian send the ring so that it will surely fall into Maria’s hands?