newlogic | Circuit Builder Desktop Application | Frontend Framework library

I am trying to access S3 from lambda(zappa+flask+python),

Here is the critical logic of my codebase:

I would need the following configuration only for my webapp:

Here is a prototypical view from the app I'm building:

The thing is, that says 100, as you would for an int- but I'd like it to say 100.00, because it's meant to represent money $- so it should always end in two decimal places. That means- essentially the representation that I'm trying to create is a float with two trailing decimal places.

So, this app itself is built in React, and the state, is created and persisted as follows, this is essentially the most important file of my program, it's called App.js:

This is the starting point of my error:

What I'm trying to do is simply take that number and perform the mathematical operation of multiplication upon it- in this case multiplying it by 0.2- however- my program contains a heinous bug which- rather than performing that operation- simply appends 20 to the string in the text box, as you can see here:

This is the code I'm trying to use to apply the operative logic, to me it seems perfectly reasonable- though admittedly I'm not a world class expert in JavaScript, nor React. Is there something blatantly wrong with the following code snippet?