What’s the viral math equation? READER'S DIGEST, GETTY IMAGES. You’ve no doubt seen this math problem (or one similar to it) making the rounds on Facebook: 4×4-4÷4+4.

With this hidden iOS 18 feature, you don't have to open your Calculator app to solve tricky equations, and you won't have to open Google to look up a conversion rate, either. Instead, you can just ...