A factory invested 2 million yuan to build a factory building, which saved 500,000 yuan compared with the original plan. What percentage was the savings?
某工厂投资200万元建厂房，比原计划节省了50万元，节省了百分之几？
<gadget id="calculator">200 + 50</gadget>
<output>250</output>

<gadget id="calculator">50 / 250</gadget>
<output>1/5 = around 0.2</output>

<result>1/5 = around 0.2</result>