Javascript to display running total and sum 2 drop downs for cart

I am a photographer that has a website to post the proof shots of each session so the client can view and purchase the photos from my website. I am adapting a purchased php script to make it do what I need. There are two tasks associated with this project. First, there are 2 drop down menus which are compiled with php code pulling from a Mysql database. The first menu shows all the print products that the client can purchase and the correlating price for that product. Using javascript I was able to get that price passed to the cart. Now, however, I would like to have the second drop down that I created for the client to choose if they would like a Color or Black and White photo to also be passed to the cart. Ultimately, I need the price from the first drop down to be summed with the price of the second drop down and then be passed to the cart. The second task is to display a running total in a textbox near the add to cart button so that when an option is chosen the price will update. At this point, I have the two drop downs populated with Mysql data and I have the print product price able to be passed to the cart, but am unable to display a running total and sum up the prices from the two drop downs and successfully pass them to the cart.

JavaScript Fotografi PHP

ID Projekti: #81283

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