Can you solve this? Tricky math riddle goes viral

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Monday, April 13, 2015
One difficult logic riddle has left many across the internet stumped.
Kennethjianwen/Facebook

Think you're smart? Then you need to check out this difficult math riddle.

A Singaporean TV presenter posted to Facebook a math/logic riddle on April 10, which quickly went viral. The riddle, which was used in the Singapore and Asian Schools Math Olympiad, asks to figure out the birthday of a woman named Cheryl with limited information.

The riddle has seemed to confuse the Internet, with many trying to decipher what day was actually Cheryl's birthday. Many were confident in their answers, while others believed there wasn't enough information presented in the question to find the solution.

But even with the limited information, there is a solution. If you want to try and solve, don't look below.

OK, are you ready? There's no turning back!

Here's the steps to figuring out the correct birthday:

Facebook User Study Room posted a detailed explanation on how to solve the puzzle.

"Out of the 10 dates, the day ranges from 14 to 19, with only 18 and 19 occurring once. If the day is Cheryl's birthday is 18 or 19, then Bernard would have known when Cheryl's birthday is since Cheryl has told him the day of her birthday.

But why does Albert know that Bernard does not know?

If Cheryl has told Albert that her birth month is May or June, then it is possible that her birthday may be May 19 or June 18. This means that Bernard may know when Cheryl's birthday is. The fact that Albert knows that Bernard does not know means that Cheryl has told Albert that her birth month is either July or August.

Initially, Bernard does not know when Cheryl's birthday is, but how did he know after Albert has first spoken?

Out of the 5 remaining dates in July and August, the day ranges from 15 to 17, with only 14 occurring twice.

If Cheryl has told Bernard the day of her birthday is 14, then Bernard would not have known. The fact that Bernard knows means the day of her birthday is not 14. So now we are left with 3 possible dates: July 16, August 15 and August 17.

After Bernard has spoken, Albert now knows when Cheryl's birthday is. If Cheryl has told Albert her birth month is August, then Albert would not have known because there are two possible dates in August.

Cheryl's birthday is on July 16."

Do you know what the answer to the math problem is? Let us know in the comments!

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