The first time a client asked, “Can this number be made with four 2s?”, I froze
That afternoon, at a café in Shenzhen, I was discussing a quote with a client working on an education project. They suddenly pointed at a budget spreadsheet and asked, “Can you express this number using only four 2s?” My first thought was: how does this connect to the quote we’re supposed to deliver? Later, I learned it was a number game their team used internally to turn abstract figures into something everyone could discuss. I got stuck too, even circling through several unnecessary steps for a simple multiplication.
This isn’t limited to math classrooms. Designers use it to warm up on a whiteboard, product managers use it to get people talking in meetings, and founders can turn it into lightweight content. In 2025, Eli Bendersky compiled a method for “making any integer with four 2s.” Teachers, engineers, and indie developers who read his blog have also used it for classroom exercises or live-stream interaction.
How it works: set the target, then work backward
The rules are simple: use exactly four 2s, combine them with addition, subtraction, multiplication, division, and parentheses, and reach a specified integer. I usually try a basic combination first, replace one part with a more complex sub-result, then adjust the divisor and parentheses. The real value isn’t producing one answer; it’s translating a client’s budget, growth rate, or date into a shared way to talk about it.
There are limits, though. This isn’t a financial tool and can’t replace a quote. For calculations that need decimal precision, I’d rather use a calculator without pretending this is something else. It works better for expressing numbers and energizing meetings than for making business decisions.
What it costs to try today: almost nothing, but leave room for trial and error
Money: ¥0, using paper and a pen or a free calculator. Time: about 20 minutes for the first attempt, then 3–5 minutes per target once I know the patterns. Technical barrier: knowing basic arithmetic and parentheses; no coding needed. First step: open a paper calculator, write down the target integer, and list the intermediate results possible with two 2s, then try combinations from left to right. For a bolder version, I treat decimals, square roots, and other rules as separate advanced levels.
If this is my first attempt, it’s fine not to try right now. It’s more like a meeting game than homework that has to be completed.
How I’d use it at each stage
If I’m just starting out and haven’t built a consistent publishing habit, I’d turn it into a short-video title around “a client throws out a spontaneous challenge” and invite viewers to post solutions. I’d make five challenges first rather than rush into a complicated content series.
If I already have 1–2 clients, I’d prepare three business-related numbers before a quote conversation and demonstrate one expression live, while keeping the game from distracting from the contract discussion.
If I’m scaling, I could package it as a team warm-up: each person contributes a target, everyone solves it under a time limit, and we turn the questions and answers into content later. Not every team needs this, but it suits teams that want the client to feel, “We’re all looking at the same sheet of paper.”