Cross worksheet average sales of unique names

[Kalemaroni]

I have 2 worksheets. Worksheet 1 has the name of the products sold and unique products column as well as Transaction ID. Worksheet 2 has the Sales and a Transaction ID that is the same as Worksheet1's Transaction ID.

I'm looking for a formula that will display the Average Sales of the Unique Product Names listed in Column C of Worksheet1 into column D of Worksheet1.

Expected value of Worksheet1!D1 is 15 ((10 + 20) / 2) and Worksheet1!D2 and D3 are 10

Worksheet1

Product	Transaction ID	Unique Product Name	Average Sales of Unique Product Name
A	B	C	D
Apples	1	Apples	=???
Apples	2	Carrots	=???
Onions	3	Onions	=???
Carrots	4

Worksheet2

Transaction ID	Sales
A	B
1	10
2	20
3	10
4	10

 

[Fluff]

Duplicate Cross worksheet average sales of unique products

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