Need help with simple Calculation formula

Hi all, i am very new to Power BI and having a difficult time solving simple formula.

I have three tables I want to use.  (Some columns are blurred out for privacy reasons)

1) FG receipt table

This is the raw data. (Among 8 columns, I only need to use 3 columns. Avail/ ReqD col., Product col., Rec/ReqQty col.,). Preferrably I do not want to touch this, as this data is stored in webserver and updated monthly

2) Product Price table

This is a reference sheet I've created, which tells you the price of each SKU

3) Summary table

This is the table I want the output to be shown in.

I want to extract goods receipt date (Avail/ ReqD column) sales qty (Rec/ ReqQty column) and SKU (product column) from FG receipt table. Here, I want to show monthly sales amount per brand (and not SKU) by multiplying sales qty (from FG receipt table) by price shown per SKU (from product price table).

The problem I'm having is, some brand (say Brand A) has multiple SKUs (ex. F00003437 & F0000338). Is there a way to extract sales amount per brand and not SKU? 

For example, on Summary table first row of Sales Actual column, I want to show total amount of sales for F00003437 and F00003438 for December 2020.

This is my first Power BI project and I've been stuck here for the past few days... Any insight would be helpful. Thank you