The sum of the upper and lower bases of a trapezoid is 36 cm, which is 4 times the height. What is the area of the trapezoid in square centimeters?
一个梯形的上、下底的和是36cm，是高的4倍，这个梯形的面积是多少平方厘米．
<gadget id="calculator">36 / 4</gadget>
<output>9</output>

<gadget id="calculator">9 / 2</gadget>
<output>9/2 = around 4.5</output>

<gadget id="calculator">36 * (9/2)</gadget>
<output>162</output>

<result>162</result>