William flew from Singapore to China to visit his grandparents. The plane departed Singapore at 18 55. It landed in China at 02 30 the next day. How long was the flight? (Singapore is in the same time zone as China)

Since 24:00 is a congruent time to 0:00,

From 18:55 -> 24:00 is 5 hours and 5 minutes

From 0:00 -> 2:30 is 2 hours and 30 minutes

Add those up and you get 7 hours and 35 minutes