Some readers may solve the problem procedurally: line up the two numbers, add the ones column, carry the one, and add the tens to get 43. Others might instead notice a creative shortcut: 29 + 14 is ...

Warning this article contains spoilers about the new Amazon Prime series Young Sherlock.

I used to impose what my kids jokingly called the “Dad tax” when they were younger. If we went out for dinner and they ordered something that looked particularly appealing, I would demand a small ...