A wire is (7/8) meters long, if (1/2) meter is used up, how many meters are left? How many columns
一根电线长(7/8)米，用去(1/2)米，还剩多少米？列式多少
<gadget id="calculator">7 / 8</gadget>
<output>7/8 = around 0.875</output>

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

<gadget id="calculator">(7/8) - (1/2)</gadget>
<output>3/8 = around 0.375</output>

<result>3/8 = around 0.375</result>