How can I get the form calculator to work properly?

One of my forms is not calculating right or not working at all. I don't know what I am or not doing to make it disfunction. 

I have checked your form and if I understand what you mean correctly, you would like to show the value of the "One-Sided" field or the "Both Sides" field on the "Total" field. 

If that's the case, here's what you need to do first:

I see that you have drop-down fields on your forms that show all the prices. 

You need to set the Calculation values for each selection for both drop-down fields. I saw that you've set Calculation Values for the "One-Sided" field but not on the "Both Sides" field.

I have checked the Form Calculation widget and found this: 

I understand that there are no computations needed on your form, you just have to show the price of the chosen Printed Side on the Total field. I would recommend for you not to use the Form Calculation widget because you are trying to get either of the values of your drop-downs and Form Calculation widget can only handle one {result 1}. 

I would suggest you use a regular TextBox field and create your own condition. 

Here's how: 

Once you've done that, you need now to create your condition using the Condition Wizard.

On the Condition Wizard, select "Update a form field value" option and click Next.

Then, 

You also do the same for "Both Sides" field.

Here are all the conditions on your form:

Another thing that you need to check is your Calculation Values and make sure it is properly set for both drop-down fields.

Add an extra 0.00 before the real Calculation Values of the drop-down fields on your form. 

Since you're using a drop-down field, there is always an empty selection that is included automatically and we need to set a value for that. Otherwise, it will just take the value of the first Calculation Value you have set.

Also, you may choose to add this Condition, so that when submitters of your form changed their mind and wants to re-select their preferred Printed Side, it will clear the "Total" field value.

I hope this helps. Please check out the cloned form I have used and feel free to clone it for your reference. Let us know, also, if you need any further assistance. Thank you.