Impossible riddle only top 10% can solve stumps many
If you’re looking to dust off the cobwebs that have built up in your brain since Christmas, this riddle might just be the thing for you. Brainteasers can be excellent tools for helping to kickstart your brain and get the cogs turning again, especially after a period of rest and mind-numbing Christmas TV specials.
Exercising your brain is just as important as the rest of your body – as a properly fit mind is more efficient at staving off diseases like dementia. Regular brain training through things like puzzles can also help boost your cognitive function, increase your problem-solving skills, and even improve your mental health.
So, if you need a mental boost today, look no further. This riddle won’t be an easy one to get you started, however, as it’s claimed that up to 90% of people struggle to get the right answer.
You’ll need to have an acute eye for detail, ace deduction skills, and a little bit of maths knowledge to get you through this fiendishly difficult puzzle.
Think you’ve got what it takes? Check it out below.
The video was shared on Instagram by Thomas Mulligan, who claimed that 90% of people are unable to solve the question despite it seeming “pretty easy” on the surface. He said the question was written by Singapore’s National Institute of Education, and is now one of the “most famous logic puzzles” in the world.
The question starts by stating that two men, Albert and Bernard, have just become friends with a woman named Cheryl. They are trying to work out her birthday, and to help them, Cheryl gives them both a list of 10 possible dates.
The dates she gives are these: May 15th, May 16th, May 19th, June 17th, June 18th, July 14th, July 16th, August 14th, August 15th, August 17th.
However, to complicate matters, Cheryl tells Albert the month she was born, and tells Bernard the day she was born – with neither of them knowing the other’s information.
Your job is to work out Cheryl’s birthday using the following statements from Albert and Bernard.
Albert says: “I don’t know when Cheryl’s birthday is, but I know that Bernard doesn’t know either.”
Bernard says: “At first I didn’t know Cheryl’s birthday, but now I know.”
Albert then replies: “Then I also know.”
Can you use this information to work out when Cheryl’s birthday is? We’ll give you the answer just below this, so don’t scroll too far and take as much time as you need to work it out.
Answer
Cheryl’s birthday is July 16th.
The puzzle is definitely tricky, but it can be worked out. Albert only knows the month Cheryl was born, but he says in his statement that he knows Bernard doesn’t know the answer with his information either – meaning the month she was born cannot be a month with a unique day in it.
This eliminates May, as Bernard would immediately know the answer if it were May 19th, and June, as the 18th doesn’t appear in any other months either.
After Albert makes that statement known, Bernard is able to work out the answer. With May and June eliminated, the answer must be the only unique date left between July and August. As the 14th and 17th appear in both months, the answer must be July 16th.
Did you manage to work it out? Let us know in the comments!
