What is the best way to create a web input form to take integer inputs, do calculations with those inputs, then display the results on the web page.

I want the user to be able to enter a set of three integer inputs with the option to add another set to input, then use one formula to calculate each nth set the user enters. I tried using CloudDeploy and RepeatingElement, but could not get the entered variables passed to the equation.

1) User enters set of values x,y,z on web input form. Option to enter n sets (plus sign to click?). 2) Plug those variables into an equation f[x,y,z_]=..... 3) Display the results for each set of inputs.