In the show Road to Olympia, besides tricky questions, there are also often tricky puzzles that require quick, logical thinking from the contestants.

One of them is the question: The notebook and the pen cost 11 thousand. The notebook is 10 thousand more expensive than the pen. So how much does the pen cost?

This question once caused a stir on social media because at first glance it seemed quite easy but many people answered it wrong. Many solutions to the problem were given.

Some people without thinking give the answer to this question as 1,000 VND, however this is not the correct answer.

If you find the answer in a short time, you are definitely a smart person. Comment on how you did it and see how many people think the same.