In September, Xiaoming’s house used 80 degrees of electricity, which was 20 degrees less than in August. How much was the savings?
小明家九月份用电80度，比八月份节约20度，节约了百分之几？
<gadget id="calculator">80 + 20</gadget>
<output>100</output>

<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

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