The fruit shop brings in 300 kilograms of apples, sells 20% of the total on the first day, and 13% of the total on the second day. How many kilograms less apples were sold on the first day than on the second day?
水果店运进300千克苹果，第一天卖出总数的20%，第二天卖出总数的13%．第一天比第二天少卖出苹果多少千克？
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">13 / 100</gadget>
<output>13/100 = around 0.13</output>

<gadget id="calculator">(1/5) - (13/100)</gadget>
<output>7/100 = around 0.07</output>

<gadget id="calculator">300 * (7/100)</gadget>
<output>21</output>

<result>21</result>