Ok, your data says "0:05" (five minutes) not "05:00" (five hours) as you mentioned, so the result is correct "0:05" (five minutes) is equal to 0.08333 hours
I was assuming that your data is in HH:MM format, could you specify what is the actual format of your data and what are the units of your desired output?
If you want to learn how to post a proper reproducible example (and use dput) check this link