It used to take 6 hours for a worker to process a machine part, but it was shortened by 2 hours after the technological innovation, how much the work efficiency has been improved.
某工人加工一个机器零件，原来要6小时，技术革新后缩短2小时，工作效率提高了多少．
<gadget id="calculator">6 - 2</gadget>
<output>4</output>

<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 / 6</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">(1/4) - (1/6)</gadget>
<output>1/12 = around 0.083333</output>

<gadget id="calculator">(1/12) / (1/6)</gadget>
<output>1/2 = around 0.5</output>

<result>1/2 = around 0.5</result>