A triangle and a parallelogram have the same area and the same height. If the base of the triangle is 9 cm, what is the base of the parallelogram in cm?
一个三角形与一个平行四边形面积相等，高也相等．如果三角形的底是9厘米，那么平行四边形的底是多少厘米．
<gadget id="calculator">9 / 2</gadget>
<output>9/2 = around 4.5</output>

<result>9/2 = around 4.5</result>