I guess the best verbal one would be to ask them to think of a number which can fit between 0.9... and 1. Then again, the proof for that is also mathematical, so I'm not sure if it would work verbally
The best mathematical proof is usually the 1/3 one, since most people can do long division, and then it's just a case of multiplying by 3, which people can do as well.
I think the most elegant proof is the infinite series one though.
The best mathematical proof is usually the 1/3 one, since most people can do long division, and then it's just a case of multiplying by 3, which people can do as well.
I think the most elegant proof is the infinite series one though.