A factory planned to make 20,000 pairs of shoes in January, but actually produced 8,500 pairs more than planned. How much was overfulfilled.
某厂一月份计划制鞋20000双，实际比计划多生产8500双．超额完成了多少．
<gadget id="calculator">8_500 / 20_000</gadget>
<output>17/40 = around 0.425</output>

<result>17/40 = around 0.425</result>