I’m trying to find a formula for calculating the elapsed time and express the result in a decimal format. For example, if i have a start time of 12:00 p and an end time of 01:30 p I would like it to express the elapsed time as 1.50 hours.
Thanks
Why? Why do you think that you were the very first to face this problem? Why didn’t you enter two words into the search bar before formulating the question? Doesn’t this or this result answer your question? Why should people you don’t even know have to write the same answers to the same questions over and over and over again? 
Yes, it had occurred to me that others had, in fact, had the same issue. And yes, I had searched beforehand and not finding what I was looking for. After a couple of hours of searching I did find what I was looking for from a post regarding OpenOffice.
Sorry, I was a little unrestrained when I wrote the comment. The fact is that recently the resource has been attacked by spammers (or spambots) and they have been using just such a technique - they search for a question among old topics, publish it again (sometimes changing the wording) and earn karma points that will allow links in comments to posts Fighting these characters takes a lot of energy Sorry again.
The simple answer to this is the following:
Let’s assume that start time is in A1 and end time is in B1. the formula would be =(B1-A1)*24.
Hope this saves someone else some time.
… provided that times belong to same day (people working on night shifts starting at 10PM and finishing an 6AM next day won’t be happy with that solution).