The sum of the upper and lower bases of a trapezoid is 15 cm, and the height is 8 cm. A triangle has the same area as the trapezoid. The base is 20 cm. What is the height in cm?
一个梯形的上、下底之和是15厘米，高是8厘米，一个三角形与这个梯形面积相等，底是20厘米，高是多少厘米．
<gadget id="calculator">8 / 2</gadget>
<output>4</output>

<gadget id="calculator">15 * 4</gadget>
<output>60</output>

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

<gadget id="calculator">60 * (1/10)</gadget>
<output>6</output>

<result>6</result>