Formula with data from other table

Hi,

I have made 3 tables and on 3rd one I would like to add data from 1st and 2nd table with formula. In maths sum from the first column of the first table and from the first column of the second table. So, here are shortcodes for each table.
Table 1: [shortcode table1]
Table 2: [shortcode table2]
Table 3: [shortcode table3]

How to put formula in a cell of table3 to:
A1 from 1st table + A1 from 2nd table = display sum value in A1 in 3rd table.

Formula?

Best regards

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