Teaching ideas of "dividing oranges": First, using the situation in the textbook, let students exchange the method of dividing oranges, which leads to the unfair method of dividing oranges on average, but it is more reasonable to divide oranges according to the proportion of the number of students, and naturally introduce students' ideas into this class, that is, discuss the problem of distribution according to a certain proportion, so that students can have sufficient experience space in the process of exploring new knowledge.
The application of proportion is proportional distribution, that is, allocating a quantity according to a certain proportion, which is the development of the average score problem. If the score is 1: 1, it is customarily called average score, and if it is 2: 1, it is proportional distribution.