The soap factory produced 1,600 boxes of soap on the first day, but on the second day, due to the increase of workers, the soap produced was four times that of the first day. How many more boxes were produced on the second day than on the first day?
肥皂厂第一天生产肥皂1600箱，第二天因工人增加，生产的肥皂是第一天的4倍．第二天比第一天多生产多少箱？
<gadget id="calculator">1_600 * 4</gadget>
<output>6_400</output>

<gadget id="calculator">6_400 - 1_600</gadget>
<output>4_800</output>

<result>4_800</result>