I came across an interesting video on YouTube that described an unusual way of estimating ⅓ of a number of items, or of a length, although that probably isn’t something most of us need to do much of the time. I was intrigued by the simplicity of the method, and of the underlying rationale for its effectiveness. The presenter based his initial example on wanting to fold his tie into thirds, so that it would fit into his carry-on luggage without having a fold in the part that would show when he wore it. But a more compelling example for me was the one he went on to illustrate, which was dividing “candies” into thirds. I’ll explain what he did in terms of the candies example, although he actually used Go counters to demonstrate. The process is shown in the video here and is worth watching. Follow it right through to the end for an ingenious way of explaining why the method works.
Another source of wonder to me.