Not everyone is great at math. But this woman trying to explain how many miles you can travel in an hour when driving 80 MPH takes math skills to a new low. Since it's a little sad, it has, predictably, blown up on Facebook overnight. But the mathematically-challenged passenger is not actually the one who sucks here. Nor is she the idiot in this video.

It's her jerk of a husband.

The woman in this video clearly doesn't grasp the simple concept of the number of miles travelled in an hour is what determines the speed, in miles per hour. It's a concept her husband could have explained to her in a few words.

Instead, he filmed her and put her on the Internet and framed it in a way that makes her look terrible. That's neither smart nor kind.

But the stupidest thing happening in this entire video is not the wife struggling to answer an easy question, it's the husband trying to film her while he drives.

You'll learn the real meaning of MPH when you crash into the side of an Arby's at 80 MPH, dumbass.

(Hat tip to Alfi1!)