Table to Table with math

First post here!  Been working with QB for awhile.   

We have a table, call it table A with some costs.   Table A has a child table, table B.   Costs are entered in table A.   There's another table, table C that has costs for the items in table B.   I'm racking my brain trying to figure how to build a pipeline (I assume this is what it needs to be, because we need table C to be the final "source" for costs) that will take the costs in table A, divide by how many child records are in table B and linked, and then create new records in table C.

Example,  I put $100 in an allocation group (table A).  There are three sub items in that allocation group (table B).   I need my user to be able to pull an item report with costs that shows $33.33 (okay bad example with the repeating) per item.  

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Jeff Hughes
Founder
pointflow.co
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