Divide a line segment into 3 parts on average, and then divide each part into 3 small parts on average. What is the size of each small part?
把一条线段平均分成3份，再把每份又平均分成3小份，每小份是它的多少．
<gadget id="calculator">1 / 3 / 3</gadget>
<output>1/9 = around 0.111111</output>

<result>1/9 = around 0.111111</result>