"The kid starts cackling, and I realise he invented his own question in order to trick me into saying it," the teacher wrote.

This math trick can help you multiply any two-digit number by 11. Arlene Resendiz is TikTok’s resident math whiz. When she’s not working as a professional tutor, she’s teaching the internet the ...

An amusing parlor trick is performed as follows. Ask spectator A to jot down any three-digit number and then to repeat the digits in the same order to make a six-digit number (e.g., 394,394). With ...