If the sum of the upper and lower bases of a trapezoid is 10 cm and the height is 5 cm, what is the area in square centimeters?
一个梯形上、下底的和是10厘米，高是5厘米，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">10 * (5/2)</gadget>
<output>25</output>

<result>25</result>