change cell formula based on first 2 numbers of another

[realniceguy5000]

Hi,

Would anyone have a script for something like this?

I'm looking at range c5:c1200

Starting at C5

If the first 2 digits in that number start with 01 then I want the formula to be in G5 = F5*12
if the first 2 digits are 03 then I want G5 = F5*24
I have several of these if statement to put in However I need it to check the entire range as well because the formula may be different in each cell (G)?

Any Idea's to get me started.

Thank You, Mike