# This Math Problem Has Gone Viral And Stumped Thousands

### Can you solve this math puzzle?

When you think of having fun, math may not be the first thing that comes to mind. But there are some math problems that people just can’t seem to get enough of.

Case in point? This seemingly simple problem that has the internet stumped:

## 9-3÷1/3+1=????

Do you think you know the answer? If so, you’re definitely one of the clever ones!

In the 1980s, 90 percent of people who tried to solve this problem got it correct. Today, a Japanese study reports only 60 percent of the people get it right.

Why? MindYourDecisions reports that most people make a common computing mistake with the fraction (1/3) in the problem. At first glance, you’d probably assume that the 1/3 is meant to be a fraction representing one-third. But, if you put the problem into a calculator or Google search, the slash would be interpreted as a division symbol, which would change the order of operations used to solve the problem, producing a different answer.

Watch the video below, which explains the common mistake that is made and how to correctly solve the problem.

Did you get the correct answer? Congrats, you’re a mathematical genius! And if you guessed wrong, don’t worry — we’re right there with you scratching our heads.

## Viral IQ Test

Now that your brain is warmed up and the wheels are turning, you might want to try some other brain teasers.

Here’s another “viral IQ test” that made the rounds on the internet. Only 1 in 1,000 people were able to solve it.

## 1+4=5

## 2+5=12

## 3+6=21

## 8+11=???

Huh?

Watch the video below for an explanation and the correct answer:

## “Teresa’s Daughter” Riddle

If you’re more into words than numbers, then you might like the “Teresa’s Daughter” riddle. This one poses the question: “If Teresa’s daughter is my daughter’s mother, then what am I to Teresa?”

The multiple choice answers are shown in the tweet below, shared by @icscontractor:

This week's #TuesdayTeaser…

If Teresa's daughter is my daughter's mother, what am I to Teresa? pic.twitter.com/SE2d67WB88

— ICS (@icscontractor) April 5, 2016

It’s a tough one! Can you figure it out. We’ll give you a moment to think.

Ready for the answer?

The correct answer is “c) Teresa’s daughter.” But that’s only if you’re a female! If you’re a male, then you would, of course, be Teresa’s son-in-law.

**RELATED:** Here Are 11 Handy Math Hacks They Didn’t Teach You In School

## Guess The Letter

Geography buffs and spelling whizzes, this one’s for you: There’s one letter of the alphabet that does not appear in the name of any of the U.S. states. Can you guess which it is?

You’re probably thinking of Z, aren’t you? Well, we’re sorry to say you’d be wrong. Because … Arizona!

Alright, what about X? It’s got to be X! Except — doh! — New Mexico and Texas (how could you forget Texas?!).

OK, so what’s the answer? It’s Q, of course!

If you didn’t have this song in your head already, here’s a refresher:

[h/t: IFL Science]