Xiao Ming’s electricity consumption was 80 degrees in October, which was 20 degrees less than last month. How much was the saving compared with last month?
小明家十月份用电80度，比上月节约了20度，比上月节约了多少
<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>