THE MOTORCYCLIST AND THE HORSEMAN A motorcyclist was sent by the post office to meet a plane at the airport. The plane landed ahead of schedule, and its mail was taken toward the post office by horse. After half an hour, the horseman met the motorcyclist on the road and gave him the mail. The motorcyclist returned to the post office $20$ minutes before he was expected. How many minutes early did the plane land? Adapted from The Moscow Puzzles by Boris Kordemsky What errors $($if any$)$ did you make while solving the problem?What problem solving strategy is best for this problem?What other problem solving strategies could have also worked, if any?What insights, into your own thinking, did you develop while working on this problem?