A new math puzzle that is supposed to be for children has been sweeping the internet because of its ability to stump adults. The puzzle originated in a third grade classroom in the Vietnamese highlands. See if you can do it yourself! 

Fill in the gaps with digits 1 through 9 to make the equation make sense when following the order of operations (multiplication, then division, then addition, and subtraction last). Remember, the colon “:” is the division sign.

The puzzle is not complicated, but according to teacher Tran Phuong, “This problem is difficult even for adults good at math, so it will be difficult for students in grades 3, and even more challenging for students in the highlands. I sent the problem to multiple people, including a person with a doctorate in economics and mathematics, but they have not given me the answer.”

Can you do it?

Watch Yeo Jin Goo, AOA’s Seolhyun, and CNBlue’s Jonghyun in Orange Marmalade, a high school vampire series based on the popular webtoon: