ExcelBanter - Convert Time to Number

I know there's a simple solution here but I don't know what it is. I have a
spreadsheet where I have created from-to times in. This is going to loosely
serve as a time sheet. Now I want to calculate the difference between the
two times to get the number of hours worked, then I want to multiply that by
the rate of pay. I have the following fields: In Time, Out Time, Total
Hours, Total Pay. The problem is, I need to be able to convert the different
in the In Time and Out time to a number once it's calculated so as to
correctly multiply by the rate of pay. For instance, if the In Time is 9:00
and the Out time is 11:30, that calculates time-wise as 2.30 which is
correct. However, to multiply it by the rate of pay, it would need to read
2.50. Any help is appreciated. I'm sure there's a simple code I can insert
somewhere to do this conversion.