The sum of the upper and lower bases of a trapezoid is 16 cm and the height is 15 cm. What is the area in square centimeters?
一个梯形上、下底的和是16厘米，高15厘米，面积是多少平方厘米．
<gadget id="calculator">15 / 2</gadget>
<output>15/2 = around 7.5</output>

<gadget id="calculator">16 * (15/2)</gadget>
<output>120</output>

<result>120</result>