triangle and a parallelogram have the same area and the same height. If the base of the triangle is 18 cm, what is the base of the parallelogram in cm?
一个三角形和一个平行四边形的面积相等，高也相等，如果三角形的底是18厘米，平行四边形的底是多少厘米．
<gadget id="calculator">18 / 2</gadget>
<output>9</output>

<result>9</result>