Calculations with Variables in Storyline

Hi everyone. I have been playing with variables and calculations in storyline a little and wonder if anyone has some good examples they would be willing to share. I have been able to get what I want but think there might be better/quicker ways. Here is what I have done:

1. create two number input variables: CurrentWeight & PercentBodyFat

2. Create three other variables: IdealWeight, Step1, Step2

3. Assign a default value of 100 to Step1

The equation I want is CurrentWeight*(100-PercentBodyFat)/0.8 = IdealWeight

I create the following triggers to a "Calculate" Button

1. Subtract PercentBodyFat from Step1 and store back to Step1

2. Divide Step1 by 100 and store back to Step1

3. Assign the CurrentWeight to Step2 (I didn't want to change the value of CurrentWeight as I might want to use it elsewhere)

4. Multiply Step2(CurrentWeight) by Step1 and store back to Step2

5. Divide Step2 by 0.8

6. Set IdealWeight equal to the value of Step2 (Don't really know why I did this...I could have just used IdealWeight in place of Step2)

7.Reassign 100 back to Step1 so I can re-enter new values and recalculate if the user wants.

Everything works fine and I get the values I want...just wonder if there are any short  cuts or best practices when doing calculations.