The school canteen used 156 kwh of electricity in May, which was 20% less than that in April. How much kwh was used in April? (Solution of column equation)
学校食堂五月份用电156度，比四月份节约了20%，四月份用电多少度？(列方程解)
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 - (1/5)</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">156 / (4/5)</gadget>
<output>195</output>

<result>195</result>