Note: You didn't specify which group user X is. So, if user X is NOT in the group of the owner for the files, the 'Other' Applies to them. If X is in the same group as the owner, the you only need to change the permssions of group. Anyway, it will become clearer as you follow the next paragraphs.
If you use Konqueror, simply edit--Select All. Right click on any of the highlighted files, select properties. Then go to permissions, and set group and others to read and execute. Then select OK.
Non gui, open a terminal, navigate to the directory and enter
chmod 755 *
Only the owner was write permission, but everyone else can read them.