A factory expanded its workshop and spent 180,000 yuan, which is 10% less than the original plan. How much was the original plan?
某工厂扩建厂房，用了18万元，比原计划节约了10%，原计划用了多少万元？
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 - (1/5)</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">18 / (4/5)</gadget>
<output>45/2 = around 22.5</output>

<result>45/2 = around 22.5</result>