Struggling with a Formula that has to do with date and time

[Tclinken]

I need a formula that has a cell which counts dwelling time in hours between: Cell A2 [=NOW() function] and [mmm dd yyyy H:mm) date format]

Example:
How long a package has been on a front door step,
in A1 [this is the date and time the package arrived], A2 [Is the =NOW() function]
I want A3 to display difference in time in hours between A2 and A1,

 

[Tclinken]

(A1) Feb 24 2018 11:57 = (A3) = 21 hours which is incorrect following the (A2) =NOW() ////// what is should be returned as is (A3) = 46 hours
(B1) Feb 23 2018 20:19 = (B3) = 13 hours which is incorrect following the (B2) =NOW() ////// What it should be returned as is (B3) = 61 hours

i've tried to read your guy's formulas i dont quite understand them like what does the "201" mean

 

[steve the fish]

You need to format your cell as [h]:mm. The 201 is just to put a comma within the string. So Feb 24 2018 becomes Feb 24, 2018. As i mentioned excel has different ways of coping with date strings depending on your location.

 

[Tclinken]

Interesting and formatting my cells did the trick so far so good, Thanks Steve