Finish my Javascript/PHP image size calculator

I have a SVG images that I need to figure out the size to. I have created 85% of the project at [login to view URL] You just need to type a price (150 total price, $35 for plate price) choose a bike in the dropdown menu (graphics4/images/models/kawikx450f-2013-2015 ) for this example. It will show rows for the different images. It will calculate the area of the image, give you a percentage of the total area, and give you a price based off of the total price you entered in. This works right now. What I need is this: If the Total price is $150 and the Plate price is $35, I want to select the checkboxes of the 3 number plates (fnp, rnp, lnp) and make their areas calculated from their totals only and the prices taken out of $35. The rest of the Total parts totals will be added up (minus the plates) and be divided from $115 ($150-$35). The total area for the parts (minus plates) would be divided by the Total price ($115) to get the price per square pixel. In graphics4/images/models/kawikx450f-2013-2015 for example, there is a ff and ff2. I want to have the checkbox for "Total" to decide what is calculated for the total bike. In this case, I would have ff be included in the total ($115). We would use the price per pixel to calculate what the total for the ff2 part that won't be included (but the price will be shown). I have attached my code. It works, but it is probably sloppy and I don't mind if you start over or add to what I have. I don't care what language you use. To Recap In addition to what I have, I just need to be able to: 1. Select what parts are Plates (will always be fnp, rnp, and lnp) and calculate their area and price from only those 3 parts. 2. Calculate the parts checked for Total to be the area (minus the Plates area and minus the Plates price) 3. Calculate the price per square pixel of the Total area and calculate the price for the parts that don't have a check on Plates or Total.