A steel pipe, if (2/5) of it is used up, there are 16 meters left; if (2/3) of it is used up, how many meters are left.
一根钢管，用去它的(2/5)，还剩16米；如果用去它的(2/3)，还剩多少米．
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 - (2/5)</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">16 / (3/5)</gadget>
<output>80/3 = around 26.666667</output>

<gadget id="calculator">2 / 3</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">1 - (2/3)</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">(80/3) * (1/3)</gadget>
<output>80/9 = around 8.888889</output>

<result>80/9 = around 8.888889</result>