I've created three groups using groupadd

groupadd sales
groupadd production
groupadd accounting

I then created 4 users and added them to a group/groups

adduser tom (added to users and sales groups)
adduser dick (added to users and production groups)
adduser hary (added to users and accounting groups)
adduser mary (added to users, sales, production, and accounting groups)

I created a directory in root named /data and place three files there (sales.rpt, prod.rpt, and acct.rpt). These files should only be accessed by the members of the correct groups, ie sales.rpt can be written to by tom and mary only but viewable everyone. I am unable to correctly figure out where to change the permissions to accomplish this. Any help would be fantastic.

umm

chmod ### yourfilename
chmod ### yourdirname

-rw------- (600) -- Only the user has read and write permissions.
-rw-r--r-- (644) -- Only user has read and write permissions; the group and others can read only.
-rwx------ (700) -- Only the user has read, write and execute permissions.
-rwxr-xr-x (755) -- The user has read, write and execute permissions; the group and others can only read and execute.
-rwx--x--x (711) -- The user has read, write and execute permissions; the group and others can only execute.
-rw-rw-rw- (666) -- Everyone can read and write to the file. Bad idea.
-rwxrwxrwx (777) -- Everyone can read, write and execute. Another bad idea.

or as root try using konquere and rght/click got properties and set permisions

hope that helps

I think he's looking for this:

ps:for exemple here, "root" is the owner and "sales" is the group
you can make the owner different then root but there is no need..

any user who is a member of sales group will now have permissions to read-write for /data/sales.rpt