Lili's house used 50 degrees of electricity last month, and this month it saved 10 degrees compared with last month. How much more did it use last month than this month?
丽丽家上月用电50度，本月比上月节约了10度，上月比本月多用了多少
<gadget id="calculator">50 - 10</gadget>
<output>40</output>

<gadget id="calculator">10 / 40</gadget>
<output>1/4 = around 0.25</output>

<result>1/4 = around 0.25</result>