A watermelon, Mingming ate (1/5), Junjun ate (3/5), how much of the watermelon did the two eat together?
一个西瓜，明明吃了(1/5)，军军吃(3/5)，两人一共吃了西瓜的几分之几？
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">3 / 5</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">(1/5) + (3/5)</gadget>
<output>4/5 = around 0.8</output>

<result>4/5 = around 0.8</result>