Removing Hours from time

Hey experts!

I have a Time data set in the format below

hh:mm:ss AM/PM

the hour are all different. What i want to do is i want the average of minutes only

lets say there are 2 values

1. 12:10:00 AM

2. 02:05:00 PM

the average minutes of these 2 values would be (10+5)/2 = 7.5 minutes

At the moment it is calculating the average including the hours.

How do i get around that?

Thanks