How can I calculate a group wise total in a silverlight datagrid?

I want group wise sub Total and at the end grand total

please provide some sample code for the same

For Example

Group  ItemID  Price  qty  total   
1         1      5     2    10
          2      3     3     9
                           ------
                            19 
2
          2      3     3     9

                           ------
                             9
                           ------

From stackoverflow

• http://forums.silverlight.net/forums/p/119135/330661.aspx

  Check this link I have posted the solution in the last.. hope it will help you.

• http://leeontech.wordpress.com/2010/02/01/summary-row-in-datagrid/