When a person runs 1000 meters, he spends 210 seconds on the first day, and his speed increases by 5% on the second day, how many seconds will the time be reduced?
某人在进行1000米跑步练习时，第一天用了210秒，第二天速度比原来提高了5%，则时间减少多少秒
<gadget id="calculator">5 / 100</gadget>
<output>1/20 = around 0.05</output>

<gadget id="calculator">1 + (1/20)</gadget>
<output>21/20 = around 1.05</output>

<gadget id="calculator">1 / (21/20)</gadget>
<output>20/21 = around 0.952381</output>

<gadget id="calculator">1 - (20/21)</gadget>
<output>1/21 = around 0.047619</output>

<gadget id="calculator">210 * (1/21)</gadget>
<output>10</output>

<result>10</result>