A grain station enters a batch of rice, sells 20% of the total on the first day, and 1/8 of the total on the second day, and sells 30 kilograms more on the first day than on the second day. How many kilograms of this batch of rice are in total?
粮站进一批大米，第一天卖出总数的20%，第二天卖出总数的(1/8)，第一天比第二天多卖出30千克，这批大米共有多少千克？
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 / 8</gadget>
<output>1/8 = around 0.125</output>

<gadget id="calculator">(1/5) - (1/8)</gadget>
<output>3/40 = around 0.075</output>

<gadget id="calculator">30 / (3/40)</gadget>
<output>400</output>

<result>400</result>