Mathcad 15 trim units

I have some empirical formulas to enter in Mathcad 15, in which the values should be inputted without units.

Is there any way to input them other that dividing the variable to his unit?

Example:

a=1m

b=2kg

I don't want to input:

c=a/1m + b/1kg = 3

I want something like:

c = "trim unit" (a+b) = 3

Note:

I want to keep the units for a and b definitions.

I don't want to define other variables.

Thanks