The area of a trapezoid is 21.6cm**2 and the height is 9cm. Two such trapezoids can be put together to form a parallelogram with a height of 9cm and a base of cm.
一个梯形的面积是21.6cm**2，高9cm，两个这样的梯形可以拼成一个高9cm，底是多少cm的平行四边形．
<gadget id="calculator">2 / 9</gadget>
<output>2/9 = around 0.222222</output>

<gadget id="calculator">21.6 * (2/9)</gadget>
<output>4.8</output>

<result>4.8</result>