I recently gave a new watch to my friend on his birthday. However, as usual with my presents, it was quite useless, as it gains 6 minutes every hour. I set it using my own accurate clock at midnight, and the watch now shows 8:26 am. I know that it stopped 30 minutes ago, so what is the correct time now?
Answer
8:10 am.
Since the watch is gaining 6 minutes every hour, for every real hour that has passed, the watch will show 66 minutes. Since the watch shows 8:26 am, we know that 506 watch minutes have passed. This, therefore, equals 460 real minutes and hence 7 hrs and 40 minutes. The watch stopped 30 minutes ago, therefore the time must now be 8:10 am.
