Respuesta :

Answer:

3:18

Step-by-step explanation:

From 3:12 PM to 5:12 PM it's 3 hours.

From 5:12 PM to 5:30 PM it's 18 minutes.

Total elapsed time: 3:18

I don't know why the question asks "what part of an hour" when the answer is more than 3 hours.