Using a specific value from an unrelated table

The common fields between the 3 tables are Automation_Month, Date, Capacity plan and location. My intention is create either a calculated column or measure for the Pre-Pro_DB table that pulls in the [Location Ratio] for a specific date and capacity plan from ReceiptsLocationRatio table. 

In the screen shots below I have the Pre-Pro_DB table showing the Automation_Count. 

I want to first match up the Automation_Month from the Pre-Pro_DB table to the Date on the ReceiptsLocationRatio.

Then I want to match up the Capacity Plan from the Pre-Pro_DB table to the Capacity Plan from the ReceiptsLocationRatio.

Then I want to specify the Location (i.e. Ireland) in the ReceiptsLocationRatio table. 

Then I want to take the LocationRatio value that matches the above from the ReceiptsLocationRatio table and multiply it by the Automation_Count from the Pre-Pro_DB table. 

Once I have all that I will need to do the same process for a different calculated column/measure using the VPH_ByLocation table. 

In excel it would be a simple process of xlookups or index but I can't figure it out here 😞