Calculations on Database Data

Question

Hi guys,

I am retriving data using a recordset and displaying it via the datagridview. I have the Item Name,Item Price,Item Quantity and Total Cost  columns. The Item Name and Item price are retrieved from the database but the Item Quantity should be entered by the user and the Total Cost should be computed by multiplying the Item Quantity and Item Price.

What kind of function class or method should I use for this ? I've tried the DataColumns but it cant seem to work out as am using the record set object for data retrieval.