After reading the story about mathematicians, I feel that mathematicians have great interest in mathematics since childhood. For example, Hua, a mathematician in China, became a famous mathematician because he was interested in mathematics and knew how to study hard. After reading the Olympic Mathematics course in the fourth grade, I feel that mathematics is very important and interesting. We should learn math well and use it to solve problems in life. The method of Olympic mathematics is very interesting and useful. For example, what is 823+92-23? It can be calculated as follows: first 823-23 equals 800, and then 92 equals 892, which is very fast. For another example, from 1 to 100? Calculate by shortcut method:1+100 =10, 2+99= 10 1, … until 50+51=/kloc-. Besides calculation, the olympiad also teaches us how to solve problems. For example, a school has newly enrolled a group of students, and the school has opened a 15 dormitory, and 34 people have no accommodation. 2 1 after the dormitory is opened, not only all the students have moved in, but also two more people can live in one dormitory. How many students are there in this group? We can arrange the two corresponding relationships given in the title together: using 15 dormitory-there are still 34 people who have no accommodation, and using 2 1 dormitory-can accommodate two more people. To find out how many students there are, we must first find out how many people can live in each dormitory. It is necessary to grasp the difference between 2 1 dormitory and 15 dormitory and the corresponding number of people. If there are two more students, 15 room will have 36 people without accommodation, and 2 1 room will be fully occupied, so the dormitory with 2 1- 15=6 (room) corresponds to 34+2=36 people, and each dormitory has 6 people. Formula: 6×2 1-2= 124 (person), and there are 124 people in this batch.