garment factory processes a batch of school uniforms for a certain school. After producing 200 sets according to the original work efficiency, because the school requires that the supply be delivered one day in advance, the garment factory needs to increase the original work efficiency by 30% to meet the requirement. If the work efficiency is increased by 20% from the beginning, the supply can be delivered one day earlier than the original schedule. How many sets of school uniforms are there in this batch?
某服装厂为某校加工一批校服，按原工作效率生产200套后，由于学校要求提前一天供货，服装厂需要把原工作效率提高30%才能达到要求．如果一开始就把工作效率提高20%，则可以比原定时间提前一天供货．这批校服有多少套？
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 + (1/5)</gadget>
<output>6/5 = around 1.2</output>

<gadget id="calculator">1 / (6/5)</gadget>
<output>5/6 = around 0.833333</output>

<gadget id="calculator">1 - (5/6)</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">1 / (1/6)</gadget>
<output>6</output>

<gadget id="calculator">30 / 100</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">1 + (3/10)</gadget>
<output>13/10 = around 1.3</output>

<gadget id="calculator">1 / (13/10)</gadget>
<output>10/13 = around 0.769231</output>

<gadget id="calculator">1 - (10/13)</gadget>
<output>3/13 = around 0.230769</output>

<gadget id="calculator">1 / (3/13)</gadget>
<output>13/3 = around 4.333333</output>

<gadget id="calculator">6 - (13/3)</gadget>
<output>5/3 = around 1.666667</output>

<gadget id="calculator">200 / (5/3)</gadget>
<output>120</output>

<gadget id="calculator">120 * 6</gadget>
<output>720</output>

<result>720</result>