The length of a rectangle is 20m and the width is 10% of the length. What is the area of the rectangle?
一个长方形的长是20m，宽是长的10%，这个长方形的面积是多少㎡．
<gadget id="calculator">10 / 100</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">20 * (1/10)</gadget>
<output>2</output>

<gadget id="calculator">20 * 2</gadget>
<output>40</output>

<result>40</result>