400
A man has to be at work 9:00am and it takes him 15 minutes to get dressed, 20 minutes to eat and 35 minutes to walk to work. What time should he get up?
7:50 am
9 hours - (15+20+35)
9 hours - 70 minutes
7 hours + 120 minutes - 70 minutes = 7 hours and 50 minutes = 7:50 am