[cynwoody]

It's trivial to cheat. Just open your browser's JavaScript console (in Chrome that's Alt-Cmd-J), type in whatever, and see the result.

Bu seriously. 18 x 18 = 325, 326, 323, or 324?? Obviously, the last digit has to be a four!

[jiggyboy]

A bunch of them are quickies via those kinds of tricks. This “quiz” might be more for showing you how you can sometimes take a short-cut during a math test than than for showing how good at math you are.