Spoiler Below I'm thinking 40 minutes. By not going 2 times the distance between the meet-up spot and the airport, the motorcyclist saved 20 minutes on his trip. The motorcycle was to be at the airport, then, 10 minutes after the moment where the motorcyclist and the horseman met up. The plane had already been at the airport for 30 minutes at the time of the meet-up, and was supposed to arrive 10 minutes later than that, so it was 40 minutes early.