A road is repaired every day (3/20), how much of it is left after repairing for 5 days.
一条公路，每天修它的(3/20)，修了5天后还剩下它的多少．
<gadget id="calculator">3 / 20</gadget>
<output>3/20 = around 0.15</output>

<gadget id="calculator">(3/20) * 5</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">1 - (3/4)</gadget>
<output>1/4 = around 0.25</output>

<result>1/4 = around 0.25</result>