Checkbox + Calculated
As in every multi-choice field, the Checkbox Field creates a list of options, and each of those options can have different values. The difference is that the user can select not one but several variants. Still, the value of the Checkbox Field can be used in the formula of Calculated Field.The values you type into the Calculated bar will be used in the formula.
If you use the macro code of the Checkbox Field in the formula, it will insert the sum of values selected by the user.
Here’s how it will look like on the frontend: