Need help with form calculation

Also, my calculations are not working, where when a user enters a number / price in the "Total Price of Tickets...." field, the software automatically takes off 15% and enters that total in the "Total Price" field.

We can help you with the calculation but we need to know the exact formula to get the total.

What is the formula needed to get the Total Price (include convenience fees)? 

Is it (number of tickets * convenience fees)? What's the fee?

I've answered it here https://www.jotform.com/answers/1291018.