Cut a watermelon into 10 pieces on average, each of the parents ate 3 pieces, and Xiaolin ate the rest. How much of the watermelon did Xiaolin eat?
把一个西瓜平均切成10块，爸爸妈妈各吃了3块，剩下的给小林吃了，小林吃了这个西瓜的几分之几？
<gadget id="calculator">10 - 3 - 3</gadget>
<output>4</output>

<gadget id="calculator">4 / 10</gadget>
<output>2/5 = around 0.4</output>

<result>2/5 = around 0.4</result>