今天的每日一题富有挑战性:三角形AOB的面积为15平方厘米,线段OB的长度为OD的3倍,则梯形ABCD的面积是多少?到现在为止,还没有一个同学想出来,只好组织同学们先讨论一下了。军军说出了大家的困惑:“这个梯形被分成了4个三角形,现在只知道其中一个三角形AOB的面积是15平方厘米,怎么求出其他3个三角形的面积呢?”芳芳提醒道:“还有一个条件——线段OB的长度为OD的3倍,它有什么作用呢?” Today’s daily challenge is challenging: triangle AOBs are 15 square centimeters and line OBs are three times longer than OD. What is the area of ​​trapezoidal ABCD? Until now, no classmate had come up with the idea of ​​organizing Students first discuss it. Jun army said everyone’s confusion: “This trapezoid was divided into 4 triangles, and now only know that one of the triangle AOB area is 15 square centimeters, how to find out the other three triangle area?” Fang Fang reminder Road: “There is also a condition - the length of the line segment OB is 3 times the OD, what does it do? ”