The store shipped in 10.5 tons of rice, sold 4.39 tons on the first day and 4.18 tons on the second day. On which day did you sell more? How many tons?
商店运进10.5吨大米，第一天卖出4.39吨，第二天卖出4.18吨．哪天卖出的多？多多少吨？
<gadget id="calculator">4.39 - 4.18</gadget>
<output>0.21</output>

<result>0.21</result>