Remove (1/5) from (3/4) tons of cement, how many tons are left?
从(3/4)吨水泥中运走(1/5)，还剩多少吨？
<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">(3/4) * (1/5)</gadget>
<output>3/20 = around 0.15</output>

<gadget id="calculator">(3/4) - (3/20)</gadget>
<output>3/5 = around 0.6</output>

<result>3/5 = around 0.6</result>