A certain factory has three workshops. The number of people in the first workshop accounts for 30% of the total number of employees in the factory. The ratio of the number of people in the second and third workshops is 5:2. It is known that the second workshop has 20 more people than the first workshop. How many employees does this factory have?
某工厂有三个车间，第一车间人数占全厂职工总数的30%，第二、三车间人数的比是5：2，已知第二车间比一车间多20人．这个工厂共有职工多少人？
<gadget id="calculator">30 / 100</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">1 - (3/10)</gadget>
<output>7/10 = around 0.7</output>

<gadget id="calculator">5 + 2</gadget>
<output>7</output>

<gadget id="calculator">5 / 7</gadget>
<output>5/7 = around 0.714286</output>

<gadget id="calculator">(7/10) * (5/7)</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">(1/2) - (3/10)</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">20 / (1/5)</gadget>
<output>100</output>

<result>100</result>