Really hope someone can help with this. 

I am building a site and need to be able to have people display a price based on their preferred option. 

To see what I mean, please look at this link where it is done perfectly: <https://swiftype.com/pricing>

...when people select monthly or yearly, the displayed price in the chart beneath changes dynamically and instantly (without page reload).

This is what I need (except with three option to choose, not one). I suspect it is jquery with dynamic divs, but I cannot make it happen. 

If anyone can help, I would be so so grateful. 

Best wishes, and thanks for your time. AB.