professional household raises 400 chickens, the number of geese is equivalent to chickens (8/5), and the number of ducks is equivalent to geese (3/4), how many ducks are there?
一个养植专业户，养鸡400只，鹅的只数相当于鸡的(8/5)，鸭的只数相当于鹅的(3/4)，鸭有多少只？
<gadget id="calculator">8 / 5</gadget>
<output>8/5 = around 1.6</output>

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

<gadget id="calculator">400 * (8/5) * (3/4)</gadget>
<output>480</output>

<result>480</result>