The sum of the upper and lower bases of a trapezoid is 24 cm and its height is 5 cm. What is its area in square centimeters?
一个梯形的上下底之和是24厘米，高是5厘米它的面积是多少平方厘米．
<gadget id="calculator">5 / 2</gadget>
<output>5/2 = around 2.5</output>

<gadget id="calculator">24 * (5/2)</gadget>
<output>60</output>

<result>60</result>