Master Wang has processed 250 parts, and 40% of them have been completed. How many parts are left?
王师傅加工250个零件，已经完成了40%，还剩下多少个？
<gadget id="calculator">40 / 100</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 - (2/5)</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">250 * (3/5)</gadget>
<output>150</output>

<result>150</result>