A piece of wood, cut off (1/4) meter for the first time, cut off the full length (1/2) for the second time, and there are 2 meters left, how long is this wood?
一根木料，第一次截去(1/4)米，第二次截去全长的(1/2)，还剩2米，这根木料有多长？
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">2 + (1/4)</gadget>
<output>9/4 = around 2.25</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">(9/4) / (1/2)</gadget>
<output>9/2 = around 4.5</output>

<result>9/2 = around 4.5</result>