There is a trapezoidal stone carving in the sea park, with an area of 47 square meters, its upper base is 6.8 meters, and its lower base is 13.2 meters. What is its height in decimeters?
海上公园有一个梯形石刻，面积是47平方米，它的上底是6.8米，下底是13.2米，它的高是多少分米．
<gadget id="calculator">6.8 + 13.2</gadget>
<output>20</output>

<gadget id="calculator">2 / 20</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">47 * (1/10) * 10</gadget>
<output>47</output>

<result>47</result>