A typist needs to type a 21,000-word manuscript, and it is planned to take 12 hours. Due to the increased typing speed, I typed 250 more words per hour. How many hours did it actually take to finish typing this manuscript?
一个打字员要打21000字的书稿，计划用12小时．由于提高了打字的速度，每小时多打250字，打完这份书稿实际用了多少小时？
<gadget id="calculator">21_000 / 12</gadget>
<output>1_750</output>

<gadget id="calculator">1_750 + 250</gadget>
<output>2_000</output>

<gadget id="calculator">21_000 / 2_000</gadget>
<output>21/2 = around 10.5</output>

<result>21/2 = around 10.5</result>