Adding Measure as dimension to existing group

I have the following data - 

ProductName,State,City,GST,Amount,Quantity
iPhone,Andhra Pradesh,Guntur,5,100,30
iPhone,Karnataka,Bangalore,10,80,20
Samsung,Andhra Pradesh,Guntur,5,75,10
Samsung,Karnataka,Bangalore,10,80,10
Xiaomi,Andhra Pradesh,Guntur,5,50,10
Xiaomi,Karnataka,Bangalore,10,30,5

I need to develop a matrix report with State, City as Rows and Amount, Quanity as Columns.  

On top of each sub group total at State level, GST row should appear and a new calculated measure Gross Total should come.

For example, say for Andhra Pradesh, the total Amount is  225, GST is 15, hence Gross would be = 225 + 15 = 240. 

Here is the output that I am expecting - 

Is this do-able? I have looked at the option of creating new dynamic table under City category but that would not give me the option for GST Total. Another way I wanted to approach the problem is by unpivoting on GST, State and try creating a join between the resultant table and 'State' table (derived automatically) but I am not able to formulate how to do. Am little new to Power BI. Could you kindly guide me how to do?