Clock calculate between 2 combo

[Bindlex]

Hello everybody,

 

I have a variable $hour

I have 2 combo where you can select the hour (for example in the first combo i select 16:00 and in the second 08:00)

When I click a button I want to calculate the number of hours between the first and the second time. (only hours, not minutes)

 

Thank you,

Regards!

[Bilgus]

Id suggest using subtraction.

[IAMK]

To add to what Bilgus said, the date is also important.
Your answer can either be 10 hours or 14 hours.