The area of a trapezoid is 10 square decimeters, the height is 4 decimeters, the upper base is 2.2 decimeters, and the lower base is how many decimeters.
一个梯形的面积是10平方分米，高是4分米，上底是2.2分米，下底是多少分米．
<gadget id="calculator">4 / 2</gadget>
<output>2</output>

<gadget id="calculator">2.2 * 2</gadget>
<output>4.4</output>

<gadget id="calculator">10 - 4.4</gadget>
<output>5.6</output>

<gadget id="calculator">5.6 / 2</gadget>
<output>2.8</output>

<result>2.8</result>