These two tables are two different table so SUM(Business) is not working. Business also inclued other entries. But here I have to show the sum of Retail and Banking only.
Where Retail & Banking are measure objects and Banking is a dimension which has different values in the report and if you are putting any report level filter and you need that amount also in the calculation , you might need to use In Report also.
=(Sum([Retail] ForAll ([Business])) In Report+Sum([Banking] ForAll ([Business])) In Report)