Summary Report Formula

Hello, I am writing, to consult the possibility of doing the following:

I have the following summary report: 





I need to know, if it is possible to generate a formula such as:

if Task = 3-Construccion make a sum of field XX --> and appear the results on Totals column

if Task = 2-Diseno make a sum of the YY field --> and appear the results on Totals column





is this possible? How?

I thank you very much for the help!