在纸上画出一条线段,如何将这条线段平均分成两份呢?我们的第一反应是:测出长度,找到中点。经过思考之后,还可以运用对折找到中点。一位小木匠就遇到了类似的问题:要把一根细木料平均分成两份,由于疏忽,唯一能测量长度的卷尺丢掉了,可是木匠只用一个没有刻度的三角板,却把 Draw a line on the paper, how to divide this line into two equally? Our first reaction is: measure the length and find the midpoint. After thinking, you can also use the fold to find the midpoint. A small carpenter encountered a similar problem: to split an average piece of fine wood into two parts, the slightest measure of length was omitted because of negligence, but the carpenter used only one square without a scale,