What-if Analysis for multiple months Fuel Spend

Hello!

I want to create a what if analysis that will calculate fuel spend each month.

Inputs:

Fuel Price, which is then converted to a fuel surcharge i.e. $4.00 is a $0.65 cents surcharge
Routes, number of shipments (Monthly)
Miles per route (Monthly)

Math breakdown::

Routes * Miles per route = Miles driven each month

Then

Miles driven each month * fuel surcharge = Fuel Spend

I would like to have it so, a user can enter a fuel price, routes, and miles per route. Then the output is a fuel spend each month based on what the user inputted.


Thank you for your ideas