How to fill an area bounded by some lines?

Question

In "Corel Draw X6" there are drawn lines which overlap ever so slightly to make it appear as a closed figure. How can I fill the area that is bounded by mentioned lines (because now it is transparent)?

Sorry for a probably silly question. I'm actually a mathematics student, not a graphics person, but I need to make some changes from time to time and university offers only fancy tools such as "Corel Draw".

Answer 1

Convert the lines to outline paths, union the filled paths into a compound path, delete the inner path. offset the path inward by half the stroke width, swap fill and stroke.

Answer 2

This is an old question, but just in case it's useful to someone else - X6 has a tool specifically for this, it's called Smart Fill, and you can find it in the toolbox. Here's a tutorial.