How Do I Write a Decimal Number?

If i write down one, one in decimal that means ten plus one or 11. But in binery it doesn't mean that. It means two plus one or three. Each successive position you have to multiply by two to the power of that position. That's the same as indecibal. The next position along is itself multiplied by to the powerof one, which is two. So zero times two is just a zero. One there, one times two is two. O forty plus three is forty three. Easy. What about your binery for forty 3? In vinary obse they are one, zero, one, zero and one. How does that work? Well, the