Xinxing Machinery Factory expanded the factory building. The original plan was to invest 4 million yuan, but the actual investment was 3.6 million yuan. What percentage was saved?
新兴机械厂扩展厂房，原计划投资400万元，实际投资360万元，节约了百分之几？
<gadget id="calculator">400 - 360</gadget>
<output>40</output>

<gadget id="calculator">40 / 400</gadget>
<output>1/10 = around 0.1</output>

<result>1/10 = around 0.1</result>