题目

I’m very happy to hear from you, but know that you are visiting China next month. I will be freely at that time and I’m eager to meet you. Please tell me your flight numbers and arrival time so I can pick up at the airport. My plan went like this. During the first week, I will take you to Beijing with a purpose of showing you around the Great Wall and much famous royal palaces. Then in the followed week, we’ll go to Yunnan Province. We can experience the traditional customs and beautiful scenery here. If you have any suggestion, please contact with me.7．化简下面各比：15：20          2.5：100          $\frac{4}{5}$：$\frac{8}{15}$          $\frac{7}{10}$：141：0.02          4：0.8          $\frac{1}{2}$：0.5          0.125：8．