In the first thank you for this sitea and I'll use a pic to express What I want because my language isn't very well.
Here are tow tables (Table2,Table3).
I want to make relationship between them Where, in the F column of Table2 will Sum the numbers in F column of Table 3 according this condition ( as it show in the pic.):

For the SIMILAR data in columns(B,C,D) between two tables
Example: Table 2 include in B,C,D data HH XX FF
There are many data (HH XX FF) in tables3 in same columns(B,C,D) so it will sum the numbers in F column that in the same row with the data (HH xx FF), and insertded the results in the in Table2 in F colmn in the same row with (HH XX FF )

Attached Images

AccessTables.JPG (47.2 KB, 3 views)

You should make append query between Table2,Table3 select same fields you want to sum and show then view it. OK

Table2,Table3

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