To build a teaching building, the planned investment is 1.5 million yuan, and the actual investment is 1.2 million yuan. How much is the actual savings compared to the plan?
建造一幢教学大楼，计划投资150万元，实际投资120万元，实际比计划节约了百分之几？
<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>