The height of a parallelogram and a trapezoid are both 6 cm, the lower base of the trapezoid and the base of the parallelogram are both 10 cm, the lower base of the trapezoid is 3 cm larger than the upper base, how much less is the area of the trapezoid than the area of the parallelogram?
一个平行四边形和一个梯形的高都是6厘米，梯形下底与平行四边形的底都是10厘米，梯形下底比上底多3厘米，梯形面积比平行四边形的面积少多少？
<gadget id="calculator">6 * 10</gadget>
<output>60</output>

<gadget id="calculator">10 - 3</gadget>
<output>7</output>

<gadget id="calculator">10 + 7</gadget>
<output>17</output>

<gadget id="calculator">6 / 2</gadget>
<output>3</output>

<gadget id="calculator">17 * 3</gadget>
<output>51</output>

<gadget id="calculator">60 - 51</gadget>
<output>9</output>

<result>9</result>