Will all records with the same ItemName have the same price (I'm going by name because you're using different Itemcode values in your example)? If so, here's what you'll do.
1. Group by ItemName.
2. Suppress the details section.
3. In the Group header put the following objects:
Summary - Min({ItemCode}, {ItemName})
ItemName
Summary - Sum({Quantity}, {ItemName})
Price
You do the summaries by clicking on the summary button (has a Sigma (big E) on it) and selecting the appropriate values.
-Dell