About one barrel of oil (1/8) is used every day, after 6 days, how much oil is left in this barrel
每天约用一桶油的(1/8)，6天后，还剩这桶油的多少
<gadget id="calculator">1 / 8</gadget>
<output>1/8 = around 0.125</output>

<gadget id="calculator">(1/8) * 6</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>