Adding percentages together?

You may need to change some of the configurations based on the intended use of the data. From what you laid out, this is just one solution to your criteria.

1. Based on your sample, there were four rows for the user to fill out the intended fields. In adding a repeating section, you can mitigate potential clutter as well as facilitate the users with a set amount higher than what is set statically

2. For your "Sum of percentages", can create the formula of SUM(<insert the name of the intended named control>)

To do this open your calculated value > Formula tab > select f(x) icon > select Runtime Functions tab > scroll to and select Sum() > select Name Controls > Select the control that holds your percentages

You can also add a validation rule to the repeating section to ensure that the user cannot submit the form with a percentage higher than 100.

To do this create the same formula as you did for your "Sum of percentages" but encapsulate it with the greaterThan() runtime function. It should look something liked this: greaterThan(Sum(PercentContributed),100). This will ensure that the user cannot submit the form with the percent total being higher than 100.

3. BONUS: You can set a formatting rule to the “Sum of percentages” calculated value with something like: equals(Sum(PercentContributed),100) and then under the formatting, you can alter how the text properties will display.

Hope this helps!