A piece of cloth is 20 meters long, first cut off 25% of it, and then cut off (1/2) meter, how many meters are cut in total.
一块布全长20米，先剪去它的25%，再剪去(1/2)米，一共剪去多少米．
<gadget id="calculator">25 / 100</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">20 * (1/4)</gadget>
<output>5</output>

<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">5 + (1/2)</gadget>
<output>11/2 = around 5.5</output>

<result>11/2 = around 5.5</result>