I'm sure this is something I shouldn't be confused about.

Here's an example. If I'm using an extension tube with a factor of 2.15 and a filter with a factor of 2.5 and I have an aperture of f4, id this the calculation or do I have this all wrong:

4 x 2.15 x 2.5 = 21.5(f22) and I adjust my shutter speed as though my aperture was f22 and then compensate for reciprocity as needed?