Is it possible to use number or a function to calculate MPH

My EMU Black is sending correct KMH (via VSS) in the gearbox over CAN to my ADU (I know its good as gps.speed is almost the same as ecu.speed). I am comfortable with functions but (n) calculations seem to not allow custom multipliers. IE (ecu.speed * 621 + 500) / 1000 which I believe would give me a rounded MPH figure.

Has anyone got a working example of how to calculate mph from ecu.speed using using the ‘number’ method in the ADU?