After using up (3/4) of a steel pipe, there are still 12 meters left. What is the original length of the steel pipe?
一根钢管用去它的(3/4)后，还剩12米，这根钢管原来长多少．
<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">12 / (1/4)</gadget>
<output>48</output>

<result>48</result>