Calculating the difference between two times

[Kim]

How do I write the formula to calculate the difference
between two times? In other words, I want to create a
formula (in Excel) that will automatically tell me:

9:30am + 10:30am = 60 minutes or 1 hr
10:30am + 10:45am = 15 minutes or .25 hours

I hope this is clear...please help!!

Thanks
K-

 

[Peo Sjoblom]

=(A2-A1)

where A2 holds 10:30 and A1 09:30