For grandma's birthday, dad bought a cake. Xiaodong ate this cake (3/10), grandma ate this cake (1/10). How much more of this cake did Xiaodong eat than grandma?
奶奶过生日，爸爸买回来一个蛋糕．小东吃了这个蛋糕的(3/10)，奶奶吃了这个蛋糕的(1/10)．小东比奶奶多吃了这个蛋糕的几分之几？
<gadget id="calculator">3 / 10</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">1 / 10</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">(3/10) - (1/10)</gadget>
<output>1/5 = around 0.2</output>

<result>1/5 = around 0.2</result>