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等量思想,是小学简易方程中列方程的基本思想。等量代换的方法,也是数学教学中常用的一种数学思维方法,不仅在求积计算中用到,而且在有些算术应用题的求解中,通过等量代换,使算理容易讲清楚,计算更简便。下面举几例说明。 [例1] 两辆汽车同时从某地出发,运送一批物资到距离165公里的工地上。甲车比乙车早到0.8小时,当甲车到达时,乙车还距工地24公里。甲车行驶全程用了多少小时? 这是一道同向行进的路程问题,解法很多,如可用小数解,也可用分数解,还能用比例解等等。但其中最简便的一种,是用等量代换的观点来解释题目中的数量关系,即甲车行完全程时间与乙车行完(165—24)公里的时间是等量。因此,算出乙车每小时的速度后,用路程除以速度,便能求
The same amount of thought is the basic idea of the column equation in the simple equation of elementary school. The method of equivalent substitution is also a kind of mathematical thinking method commonly used in mathematics teaching. It is not only used in quadrature calculation, but also easy to clarify the arithmetic by the equivalence substitution in some arithmetic application problems , Calculation easier. Here are a few examples. [Example 1] Two cars departed from somewhere at the same time and transported a batch of supplies to a site 165 kilometers away. A car earlier than 0.8 hours B, when a car arrived, B car also from the site 24 kilometers. How many hours does it take for a car to travel? This is a journey in the same direction. There are many solutions, such as available fractional solutions, fractional solutions, and proportional solutions. However, the simplest of them is to explain the relationship between quantity and quantity in the perspective of equivalence substitution, that is, the time of the complete trip of a car dealer is equivalent to that of the second car (165-24 km). Therefore, calculate the hourly rate of B car, with the distance divided by the speed, we can ask