The area of the trapezoid is 21.6 square centimeters, its height is 5.4 centimeters, its upper base is 1 cm, and its lower base is how many centimeters.
梯形的面积是21.6平方厘米，它的高是5.4厘米，上底是1厘米，下底是多少厘米．
<gadget id="calculator">2 / 5.4</gadget>
<output>0.37037</output>

<gadget id="calculator">21.6 * 0.37037</gadget>
<output>7.999992</output>

<gadget id="calculator">7.999992 - 1</gadget>
<output>6.999992</output>

<result>6.999992</result>