Hey Pableim.

You are trying to find C = A/[5.55 +- 0.02].

Now factorize this and we get:

C = [A/5.55]/[1 +- 0.02/5.55]

Let X = A/5.55, R = 0.02/5.55: Now you have something in the form of

C = X * [1 / (1 +- R)].

So in terms of standard errors this is what you have.

However: if you want to look at the above quantity in terms of a distribution then you need to find the PDF of the ratio of those two variables and if A and B are normal then you will get a Normal Ratio Distribution.