If I could change one thing in the world?

If I could change on thing in the world, I wish 30 hours in a day. Because when people ask me a favor, I always say "sorry, I have no time". I know I have time, but I just no idea how to mange my schedule of a day. In addition, we need to go to school to learning English on weekend. Of course, we have no time on weekend. We also have to working hard on workdays. After work, we still have many housework which need to do. In fact, 24 hours in a day is not enough for everyone.  We have many important thing that have to do. So someone cut down sleeping time and do not rest. If I could change I thing and save the world, I would 30 hours in a day.