The sum of the upper and lower bases of a trapezoid is 16 decimeters and the height is 6 decimeters. What is its area in square decimeters?
一个梯形的上、下底之和是16分米，高6分米，它的面积是多少平方分米．
<gadget id="calculator">6 / 2</gadget>
<output>3</output>

<gadget id="calculator">16 * 3</gadget>
<output>48</output>

<result>48</result>