How much (2/5) of 60 is equivalent to (4/5).
60的(2/5)相当于多少的(4/5)．
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">4 / 5</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">(2/5) / (4/5)</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">60 * (1/2)</gadget>
<output>30</output>

<result>30</result>