rectangular wooden board is 20 decimeters long and 3/4 wide, what is the area in square meters?
一块长方形木板，长20分米，宽是长的(3/4)，面积是多少平方米．
<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">20 * (3/4)</gadget>
<output>15</output>

<gadget id="calculator">20 * 15</gadget>
<output>300</output>

<result>300</result>