Harlowe 3.1 - Modifying Value Numbers w/ Math

So say we start off with the following:

(put: 1 into $something)

Now imagine we’ve got a variety of events that might ADD to $something. Is there a relatively simple way to just adjust a given value like that, which in the form of a number, by another given number? Basically easily increase it by specific but varying amounts based on events that occur?

Twine Version: 2.3.8
Story Format: 3.1.0

You can write (set: $something to it + 3) (or put in a variable instead of a number) but it sounds like you are probably asking a more complicated question than that?

How do your events occur? Do you click on a link? Are they on a timer? Or…?