The vegetable market shipped 4,000 kilograms of potatoes, which were sold on the first day (2/5), and those sold on the second day were the first day's (3/4). How many kilograms of potatoes are sold the next day?
菜市场运来了4000千克土豆，第一天卖出(2/5)，第二天卖出的是第一天的(3/4)．第二天卖出土豆多少千克？
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">4_000 * (2/5) * (3/4)</gadget>
<output>1_200</output>

<result>1_200</result>