Help needed with JS loop an form values

I have a small form in which a user chooses a number of tickets. This number may go up and down if the user changes their mind before they progress to the next step of the form. I need a live update in a summary Div alongside the form to calculate the total per ticket, the subtotal and the current total. Please mention the keyword, Plane, so that I know you’ve read the description please. If the number of tickets change, the summary information should change as well. As mentioned the number of tickets could go up or down. Bidding above the range will not be considered, nor will any bids high in the range