The ratio of the number of male workers to the number of female workers in a workshop is 5:4. Due to work needs, 30 female workers are transferred away. At this time, the ratio of the number of male workers to the number of female workers is 2:1. How many workers were there in this factory?
某车间男工人数和女工人数的比是5：4，因工作需要，女工人调走30人，这时男工人数与女工人数之比是2：1．这个工厂原有工人多少个？
<gadget id="calculator">4 / 5</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">(4/5) - (1/2)</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">30 / (3/10)</gadget>
<output>100</output>

<gadget id="calculator">4 + 5</gadget>
<output>9</output>

<gadget id="calculator">5 / 9</gadget>
<output>5/9 = around 0.555556</output>

<gadget id="calculator">100 / (5/9)</gadget>
<output>180</output>

<result>180</result>