There is a box of fruit, 1/4 of the total is sold on the first day, and 30% of the total is sold on the second day. At this time, the remaining fruit is 20 kg less than the sold one. How many kilograms does this box of fruit weigh?
有一箱水果，第一天卖出总数的(1/4)，第二天卖出总数的30%，这时剩下的水果比卖出的少20千克．这箱水果重多少千克？
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">30 / 100</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">(1/4) + (3/10)</gadget>
<output>11/20 = around 0.55</output>

<gadget id="calculator">1 - (11/20)</gadget>
<output>9/20 = around 0.45</output>

<gadget id="calculator">(11/20) - (9/20)</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">20 / (1/10)</gadget>
<output>200</output>

<result>200</result>