I bought a big watermelon, Dad ate (2/8) of this watermelon, and I ate (3/8) of this watermelon, what fraction of this watermelon is left?
买来一个大西瓜，爸爸吃了这个西瓜的(2/8)，我吃了这个西瓜的(3/8)，还剩下这个西瓜的几分之几？
<gadget id="calculator">2 / 8</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">3 / 8</gadget>
<output>3/8 = around 0.375</output>

<gadget id="calculator">1 - (1/4) - (3/8)</gadget>
<output>3/8 = around 0.375</output>

<result>3/8 = around 0.375</result>