Adding cells/text boxes

I have recently figured out how to program radio boxes to display a value to an associated text box. I also know how to correlate the text boxes to add up and display a total to a new text box. The issue that I am running into is if I select a different value for the radio button (there are three values/buttons), the value changes in that associated text box but the total does not update. Is there sometime of coding/calculation I can use to fix this, as opposed to using the sum selection in the calculation tab?

Thank you in advance for your time and assistance.