Price calculator by area

Hi,
I’m trying to build a form based on:
0 to 5 m² 25 €/m²
6 to 10 m² 21 €/m²
11 to 15 m² 20 €/m²
16 to 30 m² 15 €/m²
31 to 50 m² 13 €/m²

So if length*width=12 my price will be 20*12=240
is Jazzy form my solution ???

Next step is to get this price as a value in Woocommerce…
developers with a solution are invited to contact me !

Thanks,

http://wordpress.org/extend/plugins/jazzy-forms/