A triangle and a parallelogram have the same base and height. The area of the triangle is 12 square decimeters. What is the area of the parallelogram?
一个三角形与一个平行四边形等底等高，三角形的面积是12平方分米，平行四边形的面积是多少平方分米．
<gadget id="calculator">12 * 2</gadget>
<output>24</output>

<result>24</result>