For a water pipe, cut off the full length (1/4) for the first time, and cut off the remaining (1/2) for the second time, what fraction of the total length is cut off twice?
一根水管，第一次截去全长的(1/4)，第二次截去余下的(1/2)，两次共截去全长的几分之几？
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 - (1/4)</gadget>
<output>3/4 = around 0.75</output>

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

<gadget id="calculator">(3/4) * (1/2)</gadget>
<output>3/8 = around 0.375</output>

<gadget id="calculator">(1/4) + (3/8)</gadget>
<output>5/8 = around 0.625</output>

<result>5/8 = around 0.625</result>