Purchasing - Pricing for a group of Items

@ Qty

Is it feasible to calculate the Price for a group of items in Purchasing.

There are 3 items, item-A, Item-B, Item-C

If the Buyer buys a combination of the 3 items the Price break down with change,

PO with Item-A  @ Qty X = $1

PO with item-A + Item-B @ Qty X = $.9

PO with Item-A + Item-B + Item-C @ Qty Y = $.86

Is this feasible using the standard process??

Thanks in Advance.