A question of numbers (one for the maths fans)

Mod made an error in his reply mentioning a "zero" there won't be one. There is NO LAST DIGIT. We only write as many as is convenient to show what we mean. (0.9..., 0.99..., 0.999999... or whatever). They are all the same; an endless row of 9's. Trust me, you don't yet.

Nope, not this time. This time we are dealing with math and we do prove things.There is no faith. The proof has been shown to you. You do, indeed, not get it. This was answered many posts ago. It is still all.However, here we aren't talking about an infinite quantity (this was pointed out to you before too). We are talking about a representation of a finite quantity that has an infinite number of digits in it.Edited by NosyNed, : fixed spelling

They both resolve..9 is not equal to 1.
.99 is not equal to 1 but it is closer.
.999 is not equal to 1 but it is closer yet.
.9999 is not equal to 1 but it is still closer.
.999999999999999999 is not equal to 1 but it is very close indeed..9... (the ... means an endless row of 9's. We need to be VERY careful with our notation) IS equal to 1 the difference is now zero..3 is not equal to 1/3
.33 is not equal to 1/3 but is closer.
.333 is not equal fo 1/3 but it is pretty close..3... is equal to 1/3You may think there is a diffence because the first case is a whole number (1) and the second is a fraction (1/3). That doesn't make a difference to what we are talking about.

Mod should not have mentioned a zero way back there. You are correct when you say we never put it there because there is no end. There is also no 8 on the end because there isn't an end there.You might say that 2* 0.9 is 1.8 because 0.9 is 0.1 less than one and you end up doubling the missing bit less than one. 2 * .99 is 1.98 when you double the missing bit (now we re .02 less than 2).2 * 0.9... (endless 9's) is equal to 2 because there isn't any "missing bit" to double.

"is not" is a bit unclear.0.49... = 0.9... / 2 does it not?

Others have answered this but I'm not sure they got the point across..9 is 1/10 different from 1, or 0.1
.99 is 1/100 different or 0.01
.999 is 1/1000 different or 0.001
.999999 is 1/1000000 different or 0.0000001
Notice as I add 9's on the end the difference is getting very very small.With unending 9's the difference is zero..3 is 0.1 different from .4
.33 is 0.07 different from .4
.333 is 0.067 different from point 4
.3333 is 0.0667 different
.33333 is 0.06667 differentNotice that the difference is NOT getting very small.ABE the difference is not getting closer to zero it is getting closer and closer to 0.06666...Edited by NosyNed, : a little more explanation

I am dumb! I still don't get it.I define precision to be the number of digits I have.In addition you meant I presume, Technically ... does not equal .999... divided by 2 is what you meant.The precision of all the numbers you give is infinite in that they are all repeating .Thus 0.4999... is exactly equal to 0.5. So if half of .99999... is .5 it is also equal to 0.4999...Let me try the division:
2 into .9 is 0.45
2 into .99 is 0.495
2 into .999 is 0.4995and so on giving us
2 into .999 is 0.4999...Can you explain where I am confused?

It isn't helpful here. It is important not to confuse things any more than they are.But of course we would use 0.5 almost all the time.

Yes