The school built a comprehensive building, the actual investment was 1.5 million yuan, and 300,000 yuan was saved. How much was the savings?
学校建综合楼，实际投资150万元，节约了30万元，节约了几分之几？
<gadget id="calculator">150 + 30</gadget>
<output>180</output>

<gadget id="calculator">30 / 180</gadget>
<output>1/6 = around 0.166667</output>

<result>1/6 = around 0.166667</result>