Dongfang Foreign Languages School wanted to build a teaching building. The original plan was to invest 1.5 million yuan, but the actual cost was only 1.2 million yuan. How much was the savings?
东方外语学校要建一栋教学楼，原计划投资150万元，实际只用了120万元，节约了百分之几？
<gadget id="calculator">150 - 120</gadget>
<output>30</output>

<gadget id="calculator">30 / 150</gadget>
<output>1/5 = around 0.2</output>

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