Calculate a weighted average

To do this task, use the SUMPRODUCT and SUM functions.
This example calculates the average price paid for a unit across three purchases, where each purchase is for a different number of units at a different price per unit.

	A	B
	Price per unit	Number of units
1	20	500
2	25	750
3	35	200
	Formula	Description (Result)
	=SUMPRODUCT(A2:A4,B2:B4)/SUM(B2:B4)	Divides the total cost of all three orders by the total number of units ordered (24.66)

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