Custom Prioritization Calculation Zoho Desk

Custom Prioritization Calculation Zoho Desk

Hello,
I want to apply RICE prioritization by using custom functions (or maybe some other approach).

Here is a sample of what I am trying to achieve -> https://drive.google.com/file/d/19Uwjjfli23FV7-p8SiRcUspHw13dWH8f/view?usp=drivesdk

I would like to calculate the "Prioritization" custom field based on the values entered in "REACH" and "IMPACT" custom fields.

Can you please help?