weighted average formula for average discount

[Brusky]

just a simple question about weighted averages to calculate average discount percent as weighted average based on quantity of each item.

Part Number Quantity Discount 1234 1 30% 9876 25 5% ABCD 3 5% WXYZ 2 10%

Without weighting the average discount is 12.5%. But want to weight by qty. What is the best formula and where in the spreadsheet would i plug in the formula?

 

[AhoyNC]

Try:
You can put it in any blank cell you want.

Book1
	A	B	C	D	E
1	Part Number	Quantity	Discount		Wt. Average
2	1234	1	30%		6.13%
3	9876	25	5%
4	ABCD	3	5%
5	WXYZ	2	10%
Sheet1

Cell Formulas
Range	Formula
E2	E2	=SUMPRODUCT(B2:B5,C2:C5)/SUM(B2:B5)

 

[Brusky]

fantastic thanks!