The school cafeteria shipped 1,000 kilograms of rice. They ate all (1/5) on the first day and all (1/4) on the second day. How many kilograms of rice did they eat in total?
学校食堂运来1000千克大米，第一天吃了全部的(1/5)，第二天吃了全部的(1/4)，两天一共吃了多少千克的大米？
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">(1/5) + (1/4)</gadget>
<output>9/20 = around 0.45</output>

<gadget id="calculator">1_000 * (9/20)</gadget>
<output>450</output>

<result>450</result>