conversations.from: human
conversations.value: William left Missouri by 7:00 AM and arrived at his hometown by 8:00 PM. He had 3 stops of 25, 10 and 25 minutes respectively during the journey. How many hours did he spend on the road?
  How to solve this?
conversations.from: assistant
conversations.value: 8:00 PM is equivalent to 20:00 hrs so he spent a total of 20-7 = 13 hours on the journey
  He spent 25+10+25 = 60 minutes on stops
  There are 60 minutes in an hour so he spent (60/60) = 1 hour on stops
  Therefore, he spent 13-1 = 12 hours on the road.