Summing values


I am looking for some help here. I am trying to calculate a value when the following conditions are met:

If Billable = "Yes" AND Sprint = "Sprint 01" THEN SUM VALUE(Cell different sheet)/SUM ESTIMATES (this sheet where above conditions are true)*ESTIMATES value this row

I have played around with multiple different variations but feel like I am going around in circles.

=IF(Billable@row="Yes", ((IF Sprint@row, "Sprint 01", ......

The following calculation works but I don't want to have to hardcode the bold fields but to sum the values here if the two conditions above are true.

=SUM({Sysco Costs Range 2} / SUM(Estimate2, Estimate3, Estimate10, Estimate11, Estimate12, Estimate13, Estimate14, Estimate15) * Estimate2)

All help gratefully appreciated.