To build a road, the planned investment is 150,000 yuan, but the actual cost is only 120,000 yuan. How much is the savings?
修一条公路，计划投资15万元，实际只用了12万元，节约了百分之几？
<gadget id="calculator">15 - 12</gadget>
<output>3</output>

<gadget id="calculator">3 / 15</gadget>
<output>1/5 = around 0.2</output>

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