Calculating Weighted Average using Queries

[112nokia]

Hi,
How can you calculate the weighted average using a query. The weighted average should be calculated from table Dataentry, Field name "Amount", weighted by the FIrate in the same table, and than sum("amount"). --- in MS excel the formula is roughly Sumproduct( column A,Column B)/ sum(column A). Hipotetically, Column A= Amount, Column B= FIrate.

Ofoucrse I must perform this in MS Access.

Additional selection from table should be last 5 records, Using the "Dop" named column in the same table .

Help needed, please??!

 

[Remou]

How about:
[tt]SELECT Sum([Field1]*[Field2]) AS Product, Sum(Field1) AS Total, [Product]/[Total] AS Average
FROM tblTable;[/tt]