It’s been quite a year for mathematics problems on the internet. In the last few months, three questions have been online everywhere, causing consternation and head-scratching and blowing the minds of adults worldwide as examples of what kids are expected to know these days.

As a mathematician, I suppose I should subscribe to the “no such thing as bad publicity” theory, except that problems of this ilk a) usually aren’t that difficult once you get the trick b) sometimes aren’t even math problems and c) fuel the defeatist, “I’m not good at math” fire that already pervades American culture. The inability to solve such a problem quickly is certainly not indicative of a person’s overall math skill, nor should it prompt a crisis of confidence about the state of American math aptitude.

## When is Cheryl’s birthday?

In April, the internet erupted with shock that 10-year-olds in Singapore were asked to answer the following question on an exam.

Except that it wasn’t for elementary school students at all; rather it appeared on an Asian Olympiad exam designed for mathematically talented high school students. What’s more, this isn’t even a math problem, but a logic problem. It’s true that students tend to learn formal logic via mathematics (plane geometry in particular), so it is common to see problems of this type in mathematics competitions. When I was in junior high, we spent a good deal of time on these puzzles in my language arts class, and I met them again when taking the GRE prior to entering graduate school (the test contains a whole section of them).

If you’re stumped, check out a solution to the problem here.

## Vietnamese eight-year-olds do arithmetic

A month later, we heard about a third grade teacher in Vietnam who set the following puzzle for his students. Place the digits from 1 to 9 in this grid, using each only once (the : represents division).