Automate the selecting of a price from a Parent Price table based on fields in the child table.

I have built a price table that has fields type, square footage and a price in each record.

If this price table is a parent to a child table, can I automate the selection of a price record in the  Parent table with the updating of a record in the child table with a specific type and square footage? I need to automatically bring the selected price in the parent table in to the child table.

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George Bramhall
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