A number (2/5) minus (2/5) equals (2/5), what is this number?
一个数的(2/5)减去(2/5)等于(2/5)，这个数是多少？
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">(2/5) + (2/5)</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">(4/5) / (2/5)</gadget>
<output>2</output>

<result>2</result>