Need PHP code for Computed Field module field

Avg Bid (USD)
Project Budget (USD)
$30 - $250

Project Description:
Simple math operations between integer fields!
May you suggest the code in which I could replace my field names?

Math operation:
Example: 4 / 2 = 2

field_1 / field_2 = result

As a Solution I need:
1) In computed code I post:
2) In display code I post:

After testing I will send you payment immediately!

Skills required:
Drupal, PHP
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