Beleaf and Knowledge

Ludwig Wittgenstein On certinity. Questions the difference between belief and knowledge. He also bring in the phrase"what it's it like to make a mistake".

My belief on this matter:
Knowledge is when certainty it's 100%. When certainty is more than 50% it is belief. Religion is a good example, we believe that our religion is right, but we also know that there are a lot of other people who believe their religion(other religions) is right.
2x2=4 this is universal, everyone thinks it's right. We also knows that everyone thinks it's right. We say only a man out of his mind thinks it is wrong. In other words if someone mistakes and say it is wrong, we may say he it's a lunatic. Or his brain acts wrongly.
So knowledge is all propositions that everyone indisputably believe to be correct. Belief is when we think it is right, but when we know that some people thinks it is wrong.

A good example came up trying to teach maths to a dyslexic child. When I tied to teach to solve the problem, "ten apples are $100, how much is one apple?", we know to get the answer we need to divide 100 by 10. But the dyslexic son handles this in a different way. He knows it has to be either division or multiplication. Then he chose one at random, and get the answer. If a usual person who do not know how to get the result may also do it like that, but he knows it it's a mistake. But my son thinks he is right and there is no mistake, and that it it's the correct way to get the answer. Because of this he is having a learning disability, it is very difficult to teach him. He is not acquiring knowledge. Belief is irrelevant in this case, but mistake is relevant.

Take the example of 2x2=4, human brain will have lot of links about this equation. For instance there are two small boxes each having two marbles, then you pass the contents of two boxes to a bigger box, we should have four marbles. We have experience that all such experiments gives same result-4. Then our favorite maths teacher in the kindergarten taught us that it is true. There are no contradictions regarding this. Time and again this was proved correct. Then we go for a magic show, the magician performs the trick and we find 5 marbles as the result. A mistake-but still we believe 2x2=4 is correct. We know that it's a magic show, after all it's a magic show what's the use of a magic show if it shows that 2x2=4. Suppose a very trusted friend says he has experienced many times that 2x2=5, we will think he is mistaken. But suppose in a news bulletin BBC reports that a prestigious scientific lab in performing an experiment accidentally found an instance where 2x2=5. Then we will start doubting our knowledge in multiplication.

I see a link between law and knowledge. The constitution is the apex of the system. All laws flows from it.but there is no hard and fast rule in making a constitution. Constitutions of different countries differ. Some countries don't have a constitution, laws of Islamic countries are very different from other countries.
Same analogy can be drawn on different cultures of the world.
Then art and music also like that. But there is golden ratio in art, and scales in music.

Moore says "this is my hand" the knowledge of it is given as it's proof. Wittgenstein say No. What kind of proof is sufficient give example?