Yes, of course.

What do you mean by "scale"?Therefore any scale multiplied by a group of dimensionless numbers is also dimensionless.

Assuming that A, B, and C are themselves dimensionless, yes.A, B and C are arbitrary scales

x = (A/B)x' (x' is dimensionless variable),

y = Cy' (y' is dimensionless variable)

Then

xy = (AC/B)x'y' (term is also dimensionless right?)