Merge 2 XML files and modifying the attribute values

Question

I have two xml files. I want to merge them and make some arithmetic with a few attributes. Please provide some ideas. I am using a standard xslt http://informatik.hu-berlin.de/m

Answer 1

This transformation:

when applied on any XML document (not used), and having the two provided XML documents reside in:

c:/temp/delete/file1.xml:

and c:/temp/delete/file2.xml:

produces the wanted, correct result: