If (1/2) of a rope is cut off, (7/4) meters are left; if (1/2) meters are cut off, how many meters are left.
一根绳子如果剪去它的(1/2)，还剩(7/4)米；如果剪去(1/2)米，还剩多少米．
<gadget id="calculator">7 / 4</gadget>
<output>7/4 = around 1.75</output>

<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 - (1/2)</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">(7/4) / (1/2)</gadget>
<output>7/2 = around 3.5</output>

<gadget id="calculator">(7/2) - (1/2)</gadget>
<output>3</output>

<result>3</result>