A barrel of gasoline weighs 160kg, if (3/4) is used up, how many kilograms are left?
一桶汽油重160kg，用去(3/4)，还剩多少千克？
<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

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

<gadget id="calculator">160 * (1/4)</gadget>
<output>40</output>

<result>40</result>