引导学生搞清分数应用题知识问的联系及其变化规律,掌握解答方法,是提高学生解答应用题的重要方面。分数应用题的基本变化如下: 一、“分率”的变化 1.修一条路,面积是1600平方米,修了全路的3/4,修了多少平方米? 解:1600×3/4 2.修一条路,面积是1600平方米,第一天修了全路的1/2,第二天修了全路的1/4,修了多少平方米? 解:1600×(1/2+1/4) 3.修一条路,面积是1600平方米,第一 Guide students to clarify the relationship between knowledge and application of knowledge scores and the relationship between the law of change, to master the answer method is to improve students answer important questions application. The basic changes in the application of the scores are as follows: First, the “fraction” of the changes 1. Repair a road, an area of ​​1600 square meters, repair the whole road 3/4, how many square meters? Solution: 1600 × 3/4 2. Repair a road, an area of ​​1600 square meters, the first day of the repair of the whole road 1/2, the whole day to repair the road 1/4, how many square meters repair? Solution: 1600 × (1/2 +1 / 4) 3. Repair a road, the area is 1600 square meters, first