Master Wang completed a job. He originally planned to complete the task in 10 hours. After improving work efficiency, the time was shortened by 2 hours. How much work efficiency has been improved?
王师傅完成一项工作，原计划10小时完成任务，提高工作效率后时间缩短了2小时，工作效率提高了多少．
<gadget id="calculator">10 - 2</gadget>
<output>8</output>

<gadget id="calculator">1 / 8</gadget>
<output>1/8 = around 0.125</output>

<gadget id="calculator">1 / 10</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">(1/8) - (1/10)</gadget>
<output>1/40 = around 0.025</output>

<gadget id="calculator">(1/40) / (1/10)</gadget>
<output>1/4 = around 0.25</output>

<result>1/4 = around 0.25</result>