The upper base of a trapezoid is 1.8 decimeters, the lower base is 2 decimeters, and the height is 0.5 decimeters. What is its area in square decimeters?
一个梯形的上底是1.8分米，下底是2分米，高是0.5分米，它的面积是多少平方分米．
<gadget id="calculator">1.8 + 2</gadget>
<output>3.8</output>

<gadget id="calculator">0.5 / 2</gadget>
<output>0.25</output>

<gadget id="calculator">3.8 * 0.25</gadget>
<output>0.95</output>

<result>0.95</result>