how to create calculation format in acrobat?

hi, I don't have any experience with script, and I need to create a custom calculation script in my Adobe Acrobat form.

for example,we want to provide exhibitor a form, then they can choose the area they need it

Stand Zone 
□ A Zone  for Raw Space  1000/sqm
□ B Zone for Raw Space  2000/sqm
□ C Zone  for Raw Space  3000/sqm
Stand Type
□ Raw Space                        +0 /sqm
□ Shell Scheme                  +159 /sqm
□ Upgrade Shell Scheme   + 318 /sqm
□ Deluxe Shell Scheme      + 424 /sqm

Stand Open Sides :
□ One Open Side  

□ Two Open Sides  +5%
□ Three Open Sides  +8%

□ Island Booth    +10%

Stand Space (in sqm) :___________________________

the total price:

if someone choose zone B and upgrade shell scheme and three open sides.

he enter the stand space like enter 9  (manual)

The above basic price (one open side)   2318(auto)
,Total price with open side surcharge     22530.96(auto)

the total price will automatically calculation and show the number  22530.96

the detail in the backgroud is (2000+318)*9*1.08=22530.96

hope you can understand my means....my english is not good,many thanks!