What is 20 meters minus its (1/4)?
20米减去它的(1/4)后是多少．
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

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

<gadget id="calculator">20 - 5</gadget>
<output>15</output>

<result>15</result>