A watermelon is divided into 5 pieces on average, and I ate 2 pieces with a smile, how much of this watermelon I ate
一个西瓜平均分成5块，笑笑吃了2块，吃了这个西瓜的多少
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">(1/5) * 2</gadget>
<output>2/5 = around 0.4</output>

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