I believe that what is trying to be accomplished is there is two columns of aggregated data, where specific values have a relationship that must be maintained. I would suggest that you could utilize a Logical Function found here http://onlinehelp.tableau.com/current/pro/online/windows/en-us/help.html#functions_functions_logical.html?Highlight=func… . Utilize a case or if statement to add the specified amount to the correct rows of data. I have also attached a sample workbook that can be utilized to develop a solution. Take a note of how the calculated field [New Amount] is creating the corrected price for [No]=1 and how [No]=2 just shows the same price as in [Amount].
Please let me know if something is unclear or if additional questions arrive?
Test 1.twbx 10.9 KB